XVIII. Defence of Streams and Rivers…

XVIII. Defence of Streams and Rivers

Streams and large rivers, in so far as we speak of their defence, belong, like mountains, to the category of strategic barriers. But they differ from mountains in two respects. The one concerns their relative, the other their absolute defence.

Like mountains, they strengthen the relative defence; but one of their peculiarities is, that they are like implements of hard and brittle metal, they either stand every blow without bending, or their defence breaks and then ends altogether. If the river is very large, and the other conditions are favourable, then the passage may be absolutely impossible. But if the defence of any river is forced at one point, then there cannot be, as in mountain warfare, a persistent defence afterwards; the affair is finished with that one act, unless that the river itself runs between mountains.

The other peculiarity of rivers in relation to war is, that in many cases they admit of very good, and in general of better combinations than mountains for a decisive battle.

Both again have this property in common, that they are dangerous and seductive objects which have often led to false measures, and placed generals in awkward situations. We shall notice these results in examining more closely the defence of rivers.

Although history is rather bare in examples of rivers defended with success, and therefore the opinion is justified that rivers and streams are no such formidable barriers as was once supposed, when an absolute defensive system seized all means of strengthening itself which the country offered, still the influence which they exercise to the advantage of the battle, as well as of the defence of a country, cannot be denied.

In order to look over the subject in a connected form, we shall specify the different points of view from which we propose to examine it.

First and foremost, the strategic results which streams and rivers produce through their defence, must be distinguished from the influence which they have on the defence of a country, even when not themselves specially defended.

Further, the defence itself may take three different forms:—

1. An absolute defence with the main body.

2. A mere demonstration of resistance.

3. A relative resistance by subordinate bodies of troops, such as outposts, covering lines, flanking corps, etc.

Lastly, we must distinguish three different degrees or kinds of defence, in each of its forms, namely—

1. A direct defence by opposing the passage.

2. A rather indirect one, by which the river and its valley are only used as a means towards a better combination for the battle.

3. A completely direct one, by holding an unassailable position on the enemy’s side of the river.

We shall subdivide our observations, in conformity with these three degrees, and after we have made ourselves acquainted with each of them in its relation to the first, which is the most important of the forms, we shall then proceed to do the same in respect to their relations to the other two. Therefore, first, the direct defence, that is, such a defence as is to prevent the passage of the enemy’s army itself.

This can only come into the question in relation to large rivers, that is, great bodies of water.

The combinations of space, time, and force, which require to be looked into as elements of this theory of defence, make the subject somewhat complicated, so that it is not easy to gain a sure point from which to commence. The following is the result at which every one will arrive on full consideration.

The time required to build a bridge determines the distance from each other at which the corps charged with the defence of the river should be posted. If we divide the whole length of the line of defence by this distance, we get the number of corps required for the defence; if with that number we divide the mass of troops disposable, we shall get the strength of each corps. If we now compare the strength of each single corps with the number of troops which the enemy, by using all the means in his power, can pass over during the construction of his bridge, we shall be able to judge how far we can expect a successful resistance. For we can only assume the forcing of the passage to be impossible when the defender is able to attack the troops passed over with a considerable numerical superiority, say the double, before the bridge is completed. An illustration will make this plain.

If the enemy requires twenty-four hours for the construction of a bridge, and if he can by other means only pass over 20,000 men in those twenty-four hours, whilst the defender within twelve hours can appear at any point whatever with 20,000 men, in such case the passage cannot be forced; for the defender will arrive when the enemy engaged in crossing has only passed over the half of 20,000. Now as in twelve hours, the time for conveying intelligence included, we can march four miles, therefore every eight miles 20,000 men would be required, which would make 60,000 for the defence of a length of twenty-four miles of river. These would be sufficient for the appearance of 20,000 men at any point, even if the enemy attempted the passage at two points at the same time; if at only one point twice 20,000 could be brought to oppose him at that single point.

Here, then, there are three circumstances exercising a decisive influence: (1) the breadth of the river; (2) the means of passage, for the two determine both the time required to construct the bridge, and the number of troops that can cross during the time the bridge is being built; (3) the strength of the defender’s army. The strength of the enemy’s force itself does not as yet come into consideration. According to this theory we may say that there is a point at which the possibility of crossing completely stops, and that no numerical superiority on the part of the enemy would enable him to force a passage.

This is the simple theory of the direct defence of a river, that is, of a defence intended to prevent the enemy from finishing his bridge and from making the passage itself; in this there is as yet no notice taken of the effect of demonstrations which the enemy may use. We shall now bring into consideration particulars in detail, and measures requisite for such a defence.

Setting aside, in the first place, geographical peculiarities, we have only to say that the corps as proposed by the present theory, must be posted close to the river, and each corps in itself concentrated. It must be close to the river, because every position further back lengthens unnecessarily and uselessly the distance to be gone over to any point menaced; for as the waters of the river give security against any important movement on the part of the enemy, a reserve in rear is not required, as it is for an ordinary line of defence, where there is no river in front. Besides, the roads running parallel to and near a river up and down, are generally better than transverse roads from the interior leading to any particular points on the river. Lastly, the river is unquestionably better watched by corps thus placed than by a mere chain of posts, more particularly as the commanders are all close at hand.—Each of these corps must be concentrated in itself, because otherwise all the calculation as to time would require alteration. He who knows the loss of time in effecting a concentration, will easily comprehend that just in this concentrated position lies the great efficacy of the defence. No doubt, at first sight, it is very tempting to make the crossing, even in boats, impossible for the enemy by a line of posts; but with a few exceptions of points, specially favourable for crossing, such a measure would be extremely prejudicial. To say nothing of the objection that the enemy can generally drive off such a post by bringing a superior force to bear on it from the opposite side, it is, as a rule, a waste of strength, that is to say, the most that can be obtained by any such post, is to compel the enemy to choose another point of passage. If, therefore, we are not so strong that we can treat and defend the river like a ditch of a fortress, a case for which no new precept is required, such a method of directly defending the bank of a river leads necessarily away from the proposed object. Besides these general principles for positions, we have to consider—first, the examination of the special peculiarities of the river; second, the removal of all means of passage; third, the influence of any fortresses situated on the river.

A river, considered as a line of defence, must have at the extremities of the line, right and left, points d’appui, such as, for instance, the sea, or a neutral territory; or there must be other causes which make it impracticable for the enemy to turn the line of defence by crossing beyond its extremities. Now, as neither such flank supports nor such impediments are to be found, unless at considerable distances, we see at once that the defence of a river must embrace a considerable portion of its length, and that, therefore, the possibility of a defence by placing a large body of troops behind a relatively short length of the river vanishes from the class of possible facts (to which we must always confine ourselves). We say a relatively short length of the river, by which we mean a length which does not very much exceed that which the same number of troops would usually occupy on an ordinary position in line without a river. Such cases, we say, do not occur, and every direct defence of a river always becomes a kind of cordon system, at least as far as regards the extension of the troops, and therefore is not at all adapted to oppose a turning movement on the part of the enemy in the same manner which is natural to an army in a concentrated position. Where, therefore, such turning movement is possible, the direct defence of the river, however promising its results in other respects, is a measure in the highest degree dangerous.

Now, as regards the portion of the river between its extreme points, of course we may suppose that all points within that portion are not equally well suited for crossing. This subject admits of being somewhat more precisely determined in the abstract, but not positively fixed, for the very smallest local peculiarity often decides more than all which looks great and important in books. Besides, it is wholly unnecessary to lay down any rules on this subject, for the appearance of the river, and the information to be obtained from those residing near it, will always amply suffice, without referring back to books.

As matters of detail, we may observe that roads leading down upon a river, its affluents, the great towns through which it passes, and lastly above all, its islands, generally favour a passage the most; that on the other hand, the elevation of one bank over another, and the bend in the course of the river at the point of passage, which usually act such a prominent rôle in books, are seldom of any consequence. The reason of this is, that the presumed influence of these two things rests on the limited idea of an absolute defence of the river bank—a case which seldom or never happens in connection with great rivers.

Now, whatever may be the nature of the circumstances which make it easier to cross a river at particular points, they must have an influence on the position of the troops, and modify the general geometrical law; but it is not advisable to deviate too far from that law, relying on the difficulties of the passage at many points. The enemy would choose exactly those spots which are the least favourable by nature for crossing, if he knew that these are the points where there is the least likelihood of meeting us.

In any case the strongest possible occupation of islands is a measure to be recommended, because a serious attack on an island indicates in the surest way the intended point of passage.

As the corps stationed close to a river must be able to move either up or down along its banks according as circumstances require, therefore if there is no road parallel to the river, one of the most essential preparatory measures for the defence of the river is to put the nearest small roads running in a parallel direction into suitable order, and to construct such short roads of connection as may be necessary.

The second point on which we have to speak, is the removal of the means of crossing.—On the river itself the thing is no easy matter, at least requires considerable time; but on the affluents which fall into the river, particularly those on the enemy’s side, the difficulties are almost insurmountable, as these branch rivers are generally already in the hands of the enemy. For that reason it is important to close the mouths of such rivers by fortifications.

As the equipment for crossing rivers which an enemy brings with him, that is his pontoons, are rarely sufficient for the passage of great rivers, much depends on the means to be found on the river itself, its affluents, and in the great towns adjacent, and lastly, on the timber for building boats and rafts in forests near the river. There are cases in which all these circumstances are so unfavourable, that the crossing of a river is by that means almost an impossibility.

Lastly, the fortresses, which lie on both sides, or on the enemy’s side of the river, serve both to prevent any crossing at any points near them, up or down the river, and as a means of closing the mouths of affluents, as well as to receive immediately all craft or boats which may be seized.

So much as to the direct defence of a river, on the supposition that it is one containing a great volume of water. If a deep valley with precipitous sides or marshy banks, are added to the barrier of the river itself, then the difficulty of passing and the strength of the defence are certainly increased; but the volume of water is not made up for by such obstacles, for they constitute no absolute severance of the country, which is an indispensable condition of direct defence.

If we are asked what rôle such a direct river defence can play in the strategic plan of the campaign, we must admit that it can never lead to a decisive victory, partly because the object is not to let the enemy pass over to our side at all, or to crush the first mass of any size which passes; partly because the river prevents our being able to convert the advantages gained into a decisive victory by sallying forth in force.

On the other hand, the defence of a river in this way may produce a great gain of time, which is generally all important for the defensive. The collecting the means of crossing, takes up often much time; if several attempts fail a good deal more time is gained. If the enemy, on account of the river, gives his forces an entirely different direction, then still further advantages may be gained by that means. Lastly, whenever the enemy is not in downright earnest about advancing, a river will occasion a stoppage in his movements and thereby afford a durable protection to the country.

A direct defence of a river, therefore, when the masses of troops engaged are considerable, the river large, and other circumstances favourable, may be regarded as a very good defensive means, and may yield results to which commanders in modern times (influenced only by the thought of unfortunate attempts to defend rivers, which failed from insufficient means), have paid too little attention. For if, in accordance with the supposition just made (which may easily be realized in connection with such rivers as the Rhine or the Danube), an efficient defence of 24 miles of river is possible by 60,000 men in face of a very considerably superior force, we may well say that such a result deserves consideration.

We say, in opposition to a considerably superior force, and must again recur to that point. According to the theory we have propounded, all depends on the means of crossing, and nothing on the numerical strength of the force seeking to cross, always supposing it is not less than the force which defends the river. This appears very extraordinary, and yet it is true. But we must take care not to forget that most defences of rivers, or, more properly speaking, the whole, have no absolute points d’appui, therefore, may be turned, and this turning movement will be very much easier if the enemy has very superior numbers.

If now we reflect that such a direct defence of a river, even if overcome by the enemy, is by no means to be compared to a lost battle, and can still less lead to a complete defeat, since only a part of our force has been engaged, and the enemy, detained by the tedious crossing over of his troops on a single bridge, cannot immediately follow up his victory, we shall be the less disposed to despise this means of defence.

In all the practical affairs of human life it is important to hit the right point; and so also, in the defence of a river, it makes a great difference whether we rightly appreciate our situation in all its relations; an apparently insignificant circumstance may essentially alter the case, and make a measure which is wise and effective in one instance, a disastrous mistake in another. This difficulty of forming a right judgment and of avoiding the notion that “a river is a river” is perhaps greater here than anywhere else, therefore we must especially guard against false applications and interpretations; but having done so, we have also no hesitation in plainly declaring that we do not think it worth while to listen to the cry of those who, under the influence of some vague feeling, and without any fixed idea, expect everything from attack and movement, and think they see the most true picture of war in a hussar at full gallop brandishing his sword over his head.

Such ideas and feelings are not always all that is required (we shall only instance here the once famous dictator Wedel, at Züllichau, in 1759); but the worst of all is that they are seldom durable, and they forsake the general at the last moment if great complex cases branching out into a thousand relations bear heavily upon him.

We therefore believe that a direct defence of a river with large bodies of troops, under favourable conditions, can lead to successful results if we content ourselves with a moderate negative: but this does not hold good in the case of smaller masses. Although 60,000 men on a certain length of river could prevent an army of 100,000 or more from passing, a corps of 10,000 on the same length would not be able to oppose the passage of a corps of 10,000 men, indeed, probably, not of one half that strength if such a body chose to run the risk of placing itself on the same side of the river with an enemy so much superior in numbers. The case is clear, as the means of passing do not alter.

We have as yet said little about feints or demonstrations of crossing, as they do not essentially come into consideration in the direct defence of a river, for partly such defence is not a question of concentration of the army at one point, but each corps has the defence of a portion of the river distinctly allotted to it; partly such simulated intentions of crossing are also very difficult under the circumstances we have supposed. If, for instance, the means of crossing in themselves are already limited, that is, not in such abundance as the assailant must desire to ensure the success of his undertaking, he will then hardly be able or willing to apply a large share to a mere demonstration: at all events the mass of troops to be passed over at the true point of crossing must be so much the less, and the defender gains again in time what through uncertainty he may have lost.

This direct defence, as a rule, seems only suitable to large rivers, and on the last half of their course.

The second form of defence is suitable for smaller rivers with deep valleys, often also for very unimportant ones. It consists in a position taken up further back from the river at such a distance that the enemy’s army may either be caught in detail after the passage (if it passes at several points at the same time) or if the passage is made by the whole at one point, then near the river, hemmed in upon one bridge and road. An army with the rear pressed close against a river or a deep valley, and confined to one line of retreat, is in a most disadvantageous position for battle; in the making proper use of this circumstance, consists precisely the most efficacious defence of rivers of moderate size, and running in deep valleys.

The disposition of an army in large corps close to a river which we consider the best in a direct defence, supposes that the enemy cannot pass the river unexpectedly and in great force, because otherwise, by making such a disposition, there would be great danger of being beaten in detail. If, therefore, the circumstances which favour the defence are not sufficiently advantageous, if the enemy has already in hand ample means of crossing, if the river has many islands or fords, if it is not broad enough, if we are too weak, etc., etc., then the idea of that method may be dismissed: the troops for the more secure connection with each other must be drawn back a little from the river, and all that then remains to do is to ensure the most rapid concentration possible upon that point where the enemy attempts to cross, so as to be able to attack him before he has gained so much ground that he has the command of several passages. In the present case the river or its valley must be watched and partially defended by a chain of outposts whilst the army is disposed in several corps at suitable points and at a certain distance (usually a few leagues) from the river.

The most difficult point lies here in the passage through the narrow way formed by the river and its valley. It is not now only the volume of water in the river with which we are concerned, but the whole of the defile, and, as a rule, a deep rocky valley is a greater impediment to pass than a river of considerable breadth. The difficulty of the march of a large body of troops through a long defile is in reality much greater than appears at first consideration. The time required is very considerable; and the danger that the enemy during the march may make himself master of the surrounding heights must cause disquietude. If the troops in front advance too far, they encounter the enemy too soon, and are in danger of being overpowered; if they remain near the point of passage then they fight in the worst situation. The passage across such an obstacle of ground with a view to measure strength with the enemy on the opposite side is, therefore, a bold undertaking, or it implies very superior numbers and great confidence in the commander.

Such a defensive line cannot certainly be extended to such a length as in the direct defence of a great river, for it is intended to fight with the whole force united, and the passages, however difficult, cannot be compared in that respect with those over a large river; it is, therefore, much easier for the enemy to make a turning movement against us. But at the same time, such a movement carries him out of his natural direction (for we suppose, as is plain in itself, that the valley crosses that direction at about right angles), and the disadvantageous effect of a confined line of retreat only disappears gradually, not at once, so that the defender will still always have some advantage over the advancing foe, although the latter is not caught exactly at the crisis of the passage, but by the detour he makes is enabled to get a little more room to move.

As we are not speaking of rivers in connection only with the mass of their waters, but have rather more in view the deep cleft or channel formed by their valleys, we must explain that under the term we do not mean any regular mountain gorge, because then all that has been said about mountains would be applicable. But, as every one knows, there are many level districts where the channels of even the smallest streams have deep and precipitous sides; and, besides these, such as have marshy banks, or whose banks are otherwise difficult of approach, belong to the same class.

Under these conditions, therefore, an army on the defensive, posted behind a large river or deep valley with steep sides, is in a very excellent position, and this sort of river defence is a strategic measure of the best kind.

Its defect (the point on which the defender is very apt to err) is the over-extension of the defending force. It is so natural in such a case to be drawn on from one point of passage to another, and to miss the right point where we ought to stop; but then, if we do not succeed in fighting with the whole army united, we miss the intended effect; a defeat in battle, the necessity of retreat, confusion in many ways and losses reduce the army nearly to ruin, even although the resistance has not been pushed to an extremity.

In saying that the defensive, under the above conditions, should not extend his forces widely, that he should be in any case able to assemble all his forces on the evening of the day on which the enemy passes, enough is said, and it may stand in place of all combinations of time, power, and space, things which, in this case, must depend on many local points.

The battle to which these circumstances lead must have a special character—that of the greatest impetuosity on the side of the defender. The feigned passages by which the enemy will keep him for some time in uncertainty—will, in general prevent his discovering the real point of crossing a moment too soon. The peculiar advantages of the situation of the defender consist in the disadvantageous situation of the enemy’s corps just immediately in his front; if other corps, having passed at other points, menace his flank, he cannot, as in a defensive battle, counteract such movements by vigorous blows from his rear, for that would be to sacrifice the above-mentioned advantage of his situation; he must, therefore, decide the affair in his front before such other corps can arrive and become dangerous, that is, he must attack what he has before him as swiftly and vigorously as possible, and decide all by its defeat.

But the object of this form of river defence can never be the repulse of a very greatly superior force, as is conceivable in the direct defence of a large river; for as a rule we have really to deal with the bulk of the enemy’s force, and although we do so under favourable circumstances, still it is easy to see the relation between the forces must soon be felt.

This is the nature of the defence of rivers of a moderate size and deep valleys when the principal masses of the armies are concerned, for in respect to them the considerable resistance which can be offered on the ridges or scarps of the valley stands no comparison with the disadvantages of a scattered position, and to them a decisive victory is a matter of necessity. But if nothing more is wanted but the reinforcement of a secondary line of defence which is intended to hold out for a short time, and which can calculate on support, then certainly a direct defence of the scarps of the valley, or even of the river bank, may be made; and although the same advantages are not to be expected here as in mountain positions, still the resistance will always last longer than in an ordinary country. Only one circumstance makes this measure very dangerous, if not impossible: it is when the river has many windings and sharp turnings, which is just what is often the case when a river runs in a deep valley, Only look at the course of the Mosel. In a case of its defence, the corps in advance on the salients of the bends would almost inevitably be lost in the event of a retreat.

That a great river allows the same defensive means, the same form of defence, which we have pointed out as best suited for rivers of a moderate size, in connection with the mass of an army, and also under much more favourable circumstances, is plain of itself. It will come into use more especially when the point with the defender is to gain a decisive victory (Aspern).

The case of an army drawn up with its front close on a river, or stream, or deep valley, in order by that means to command a tactical obstacle to the approach to its position, or to strengthen its front, is quite a different one, the detailed examination of which belongs to tactics. Of the effect of this we shall only say this much, that it is founded on a delusion.—If the cleft in the ground is very considerable, the front of the position becomes absolutely unassailable. Now, as there is no more difficulty in passing round such a position than any other, it is just the same as if the defender had himself gone out of the way of the assailant, yet that could hardly be the object of the position. A position of this kind can, therefore, only be advisable when, as a consequence of its position, it threatens the communications of the assailant, so that every deviation by him from the direct road is fraught with consequences altogether too serious to be risked.

In this second form of defence, feigned passages are much more dangerous, for the assailant can make them more easily, while, on the other hand, the proposition for the defender is, to assemble his whole army at the right point. But the defender is certainly not quite so much limited for time here, because the advantage of his situation lasts until the assailant has massed his whole force, and made himself master of several crossings; moreover, also, the simulated attack has not the same degree of effect here as in the defence of a cordon, where all must be held, and where, therefore, in the application of the reserve, it is not merely a question, as in our proposition, where the enemy has his principal force, but the much more difficult one, Which is the point he will first seek to force?

With respect to both forms of defence of large and small rivers, we must observe generally, that if they are undertaken in the haste and confusion of a retreat, without preparation, without the removal of all means of passage, and without an exact knowledge of the country, they cannot certainly fulfil what has been here supposed; in most such cases, nothing of the kind is to be calculated upon; and therefore it will be always a great error for an army to divide itself over extended positions.

As everything usually miscarries in war, if it is not done upon clear convictions and with the whole will and energy, so a river defence will generally end badly when it is only resorted to because we have not the heart to meet the enemy in the open field, and hope that the broad river or the deep valley will stop him. When that is the case, there is so little confidence in the actual situation that both the general and his army are usually filled with anxious forebodings, which are almost sure to be realized quick enough. A battle in the open field does not suppose a perfectly equal state of circumstances beforehand, like a duel; and the defender who does not know how to gain for himself any advantages, either through the special nature of the defence, through rapid marches, or by knowledge of the country and freedom of movement, is one whom nothing can save, and least of all will a river or its valley be able to help him.

The third form of defence—by a strong position taken up on the enemy’s side of the river—founds its efficacy on the danger in which it places the enemy of having his communications cut by the river, and being thus limited to some bridges. It follows, as a matter of course, that we are only speaking of great rivers with a great volume of water, as these alone can lead to such results, whilst a river which is merely in a deep ravine usually affords such a number of passages that all danger of the above disappears.

But the position of the defensive must be very strong, almost unassailable; otherwise he would just meet the enemy half way, and give up his advantages. But if it is of such strength that the enemy resolves not to attack it, he will, under certain circumstances, be confined thereby to the same bank with the defender. If the assailant crosses, he exposes his communications; but certainly, at the same time, he threatens ours. Here, as in all cases in which one army passes by another, the great point is, whose communications, by their number, situation, and other circumstances, are the best secured, and which has also, in other respects, most to lose, therefore can be outbid by his opponent; lastly, which possesses still in his army the most power of victory upon which he can depend in an extreme case. The influence of the river merely amounts to this, that it augments the danger of such a movement for both parties, as both are dependent on bridges. Now, in so far as we can assume that, according to the usual course of things, the passage of the defender, as well as of his depôts of all kinds, are better secured by fortresses than those of the offensive, in so far is such a defence conceivable, and one which might be substituted for the direct defence when circumstances are not favourable to that form. Certainly then the river is not defended by the army, nor the army by the river, but by the connection between the two the country is defended, which is the main point.

At the same time it must be granted that this mode of defence, without a decisive blow, and resembling the state of tension of two electric currents, of which the atmospheres only are as yet in contact, cannot stop any very powerful impulsive force. It might be applicable against even a great superiority of force on the side of the enemy, if their army is commanded by a cautious general, wanting in decision, and never disposed to push forward with energy; it might also answer when a kind of oscillation towards equality between the contending forces has previously arisen, and nothing but small advantages are looked for on either side. But if we have to deal with superior forces, led by a bold general, we are upon a dangerous course, very close to an abyss.

This form of defence looks so bold, and at the same time so scientific, that it might be called the elegant; but as elegance easily merges into folly, and as it is not so easily excused in war as in society, therefore we have had as yet few instances of this elegant art. From this third mode a special means of assistance for the first two forms is developed, that is, by the permanent occupation of a bridge and a tête du pont to keep up a constant threat of crossing.

Besides the object of an absolute defence with the main body, each of the three modes of defence may also have that of a feigned defence.

This show of a resistance, which it is not intended really to offer, is an act which is combined with many other measures, and fundamentally with every position which is anything more than a camp of route; but the feigned defence of a great river becomes a complete stratagem in this way, that it is necessary to adopt actually more or less a number of measures of detail, and that its action is usually on a greater scale and of longer duration than that of any other; for the act of passing a great river in sight of an army is always an important step for the assailant, one over which he often ponders long, or which he postpones to a more favourable moment.

For such a feigned defence it is therefore requisite that the main army should divide and post itself along the river, (much in the same manner as for a real defence); but as the intention of a mere demonstration shows that circumstances are not favourable enough for a real defence, therefore, from that measure as it always occasions a more or less extended and scattered disposition, the danger of serious loss may very easily arise if the corps should get engaged in a real resistance, even if not carried to an extremity; it would then be in the true sense a half measure. In a demonstration of defence, therefore, arrangement must be made for a sure concentration of the army at a point considerably (perhaps several days’ march) in rear, and the defence should not be carried beyond what is consistent with this arrangement.

In order to make our views plainer, and to show the importance of such a defensive demonstration, let us refer to the end of the campaign of 1813. Buonaparte repassed the Rhine with forty or fifty thousand men. To attempt to defend this river with such a force at all points where the Allies, according to the direction of their forces, might easily pass, that is, between Manheim and Nimeguen, would have been to attempt an impossibility. The only idea which Buonaparte could therefore entertain was to offer his first real resistance somewhere on the French Meuse, where he could make his appearance with his army in some measure reinforced. Had he at once withdrawn his forces to that point, the Allies would have followed close at his heels; had he placed his army in cantonments for rest behind the Rhine, the same thing must have taken place almost as soon, for at the least show of desponding caution on his part, the Allies would have sent over swarms of Cossacks and other light troops in pursuit, and, if that measure produced good results, other corps would have followed. The French corps had therefore nothing for it but to take steps to defend the Rhine in earnest. As Buonaparte could foresee that this defence must end in nothing whenever, the Allies seriously undertook to cross the river, it may therefore be regarded in the light of a mere demonstration, in which the French corps incurred hardly any danger, as their point of concentration lay on the Upper Moselle. Only Macdonald, who, as is known, was at Nimeguen with twenty thousand men, committed a mistake in deferring his retreat till fairly compelled to retire, for this delay prevented his joining Buonaparte before the battle of Brienne, as the retreat was not forced on him until after the arrival of Winzurgerode’s corps in January. This defensive demonstration on the Rhine, therefore, produced the result of checking the Allies in their advance, and induced them to postpone the crossing of the river until their reinforcements arrived, which did not take place for six weeks. These six weeks were of infinite value to Buonaparte. Without this defensive demonstration on the Rhine, Paris would have become the next immediate object after the victory of Leipsic, and it would have been impossible for the French to have given battle on that side of their capital.

In a river defence of the second class, therefore, in that of rivers of a smaller size, such demonstrations may also be used, but they will generally be less effectual, because mere attempts to cross are in such a case easier, and therefore the spell is sooner broken.

In the third kind of river defence, a demonstration would in all probability be still less effectual, and produce no more result than that of the occupation of any other temporary position.

Lastly, the two first forms of defence are very well suited to give a chain of outposts, or any other defensive line (cordon) established for a secondary object, or to a corps of observation, much greater and more reliable strength than it would have without the river. In all these cases the question is limited to a relative resistance, and that must naturally be considerably strengthened by such a great natural obstacle. At the same time, we must not think only of the relative quantity of time gained by the resistance in fight in a case of this sort, but also of the many anxieties which such undertakings usually excite in the mind of the enemy, and which in ninety-nine cases out of a hundred lead to his giving up his plans if not urged or pressed by necessity.

XIX. Defence of Streams and Rivers (continued)

We have still to add something respecting the influence of streams and rivers on the defence of a country, even when they are not themselves defended.

Every important river, with its main valley and its adjacent valleys, forms a very considerable obstacle in a country, and in that way it is, therefore, advantageous to defence in general; but its peculiar influence admits of being more particularly specified in its principal effects.

First we must distinguish whether it flows parallel to the frontier, that is, the general strategic front, or at an oblique or a right angle to it. In the case of the parallel direction we must observe the difference between having our own army or that of the enemy behind it, and in both cases again the distance between it and the army.

An army on the defensive, having behind it a large river within easy reach (but not less than a day’s march), and on that river an adequate number of secure crossings, is unquestionably in a much stronger situation than it would be without the river; for if it loses a little in freedom of movement by the requisite care for the security of the crossings, still it gains much more by the security of its strategic rear, that means chiefly of its lines of communication. In all this we allude to a defence in our own country; for in the enemy’s country, although his army might be before us, we should still have always more or less to apprehend his appearance behind us on the other side of the river, and then the river, involving as it does narrow defiles in roads, would be more disadvantageous than otherwise in its effect on our situation. The further the river is behind the army, the less useful it will be, and at certain distances its influence disappears altogether.

If an advancing army has to leave a river in its rear, the river cannot be otherwise than prejudicial to its movements, for it restricts the communications of the army to a few single passages. When Prince Henry marched against the Russians on the right bank of the Oder near Breslau, he had plainly a point d’appui in the Oder flowing behind him at a day’s march; on the other hand, when the Russians under Cznernitschef passed the Oder subsequently, they were in a very embarrassing situation, just through the risk of losing their line of retreat, which was limited to one bridge.

If a river crosses the theatre of war more or less at a right angle with the strategic front, then the advantage is again on the side of the defensive; for, in the first place, there are generally a number of good positions leaning on the river, and covered in front by the transverse valleys connected with the principal valley (like the Elbe for the Prussians in the Seven Years’ War); secondly, the assailant must leave one side of the river or the other unoccupied, or he must divide his forces; and such division cannot fail to be in favour again of the defensive, because he will be in possession of more well secured passages than the assailant. We need only cast a glance over the whole Seven Years’ War, to be convinced that the Oder and Elbe were very useful to Frederick the Great in the defence of his theatre of war (namely Silesia, Saxony and the Mark), and consequently a great impediment to the conquest of these provinces by the Austrians and Russians, although there was no real defence of those rivers in the whole Seven Years’ War, and their course is mostly, as connected with the enemy, at an oblique or a right angle rather than parallel with the front.

It is only the convenience of a river as a means of transport, when its course is more or less in a perpendicular direction, which can, in general, be advantageous to the assailant; in that respect it may be so for this reason, that as he has the longer line of communication, and, therefore, the greater difficulty in the transport of all he requires, water carriage may relieve him of a great deal of trouble and prove very useful. The defender, on his side, certainly has it in his power to close the navigation within his own frontier by fortresses; still even by that means the advantages which the river affords the assailant will not be lost so far as regards its course up to that frontier. But if we reflect upon the fact that many rivers are often not navigable, even where they are of no unimportant breadth as respects other military relations, that others are not navigable at all seasons, that the ascent against the stream is tedious, that the winding of a river often doubles its length, that the chief communications between countries now are high roads, and that now more than ever the wants of an army are supplied from the country adjacent to the scene of its operations, and not by carriage from distant parts,—we can well see that the use of a river does not generally play such a prominent part in the subsistence of troops as is usually represented in books, and that its influence on the march of events is therefore very remote and uncertain.

XX. A. Defence of Swamps

Very large wide swamps, such as the Bourtang Moor in North Germany, are so uncommon that it is not worth while to lose time over them; but we must not forget that certain lowlands and marshy banks of small rivers are more common, and form very considerable obstacles of ground which may be, and often have been, used for defensive purposes.

Measures for their defence are certainly very like those for the defence of rivers, at the same time there are some peculiarties to be specially noticed. The first and principal one is, that a marsh which except on the causeway is impracticable for infantry is much more difficult to cross than any river; for, in the first place, a causeway is not so soon built as a bridge; secondly, there are no means at hand by which the troops to cover the construction of the dyke or causeway can be sent across. No one would begin to build a bridge without using some of the boats to send over an advanced guard in the first instance; but in the case of a morass no similar assistance can be employed; the easiest way to make a crossing for infantry over a morass is by means of planks, but when the morass is of some width, this is a much more tedious process than the crossing of the first boats on a river. If now, besides, there is in the middle of the morass a river which cannot be passed without a bridge, the crossing of the first detachment of troops becomes a still more difficult affair, for although single passengers may get across on boards, the heavy material required for bridge building cannot be so transported. This difficulty on many occasions may be insurmountable.

A second peculiarity of a swamp is, that the means used to cross cannot be completely removed like those, used for passing a river; bridges may be broken, or so completely destroyed that they can never be used again; the most that can be done with dykes is to cut them, which is not doing much. If there is a river in the middle, the bridge can of course be taken away, but the whole passage will not by that means be destroyed in the same degree as that of a large river by the destruction of a bridge. The natural consequence is that dykes which exist must always be occupied in force and strenuously defended if we desire to derive any general advantage from the morass.

On the one hand, therefore, we are compelled to adopt a local defence, and on the other, such a defence is favoured by the difficulty of passing at other parts. From these two peculiarities the result is, that the defence of a swamp must be more local and passive than that of a river.

It follows from this that we must be stronger in a relative degree than in the direct defence of a river, consequently that the line of defence must not be of great length, especially in cultivated countries, where the number of passages, even under the most favourable circumstances for defence, is still very great.

In this respect, therefore, swamps are inferior to great rivers, and this is a point of great importance, for all local defence is illusory and dangerous to an extreme. But if we reflect that such swamps and low grounds generally have a breadth with which that of the largest rivers in Europe bears no comparison, and that consequently a post stationed for the defence of a passage is never in danger of being overpowered by the fire from the other side, that the effects of its own fire over a long narrow dyke is greatly increased, and that the time required to pass such a defile, perhaps a quarter or half a mile long, is much longer than would suffice to pass an ordinary bridge: if we consider all this, we must admit that such low lands and morasses, if means of crossing are not too numerous, belong to the strongest lines of defence which can be formed.

An indirect defence, such as we made ourselves acquainted with in the case of streams and rivers, in which obstacles of ground are made use of to bring on a great battle under advantageous circumstances, is generally quite as applicable to morasses.

The third method of a river-defence by means of a position on the enemy’s side would be too hazardous on account of the toilsome nature of the crossing.

It is extremely dangerous to venture on the defence of such morasses, soft meadows, bogs, etc., as are not quite impassable beyond the dykes. One single line of crossing discovered by the enemy is sufficient to pierce the whole line of defence which, in case of a serious resistance, is always attended with great loss to the defender.

B. Inundations

Now we have still to consider inundations. As defensive means and also as phenomena in the natural world they have unquestionably the nearest resemblance to morasses.

They are not common certainly; perhaps Holland is the only country in Europe where they constitute a phenomenon which makes them worth notice in connection with our object; but just that country, on account of the remarkable campaigns of 1672 and 1787, as well as on account of its important relation in itself to both France and Germany, obliges us to devote some consideration to this matter.

The character of these Dutch inundations differs from ordinary swampy and impassable wet low lands in the following respects:

1. The soil itself is dry and consists either of dry meadows or of cultivated fields.

2. For purposes of irrigation or of drainage, a number of small ditches of greater or loss depth and breadth intersect the country in such a way that they may be seen running in lines in parallel directions.

3. Larger canals, inclosed by dykes and intended for irrigation, drainage, and transit of vessels, run through the country in all possible directions and are of such a size that they can only be passed on bridges.

4. The level of the ground throughout the whole district subject to inundation, lies perceptibly under the level of the sea, therefore, of course, under that of the canals.

5. The consequence of this is, that by means of cutting the dams, closing and opening the sluices, the whole country can be laid under water, so that there are no dry roads except on the tops of the dykes, all others being either entirely under water or, at least, so soaked that they become no longer fit for use. Now, if even the inundation is only three or four feet deep, so that, perhaps, for short distances it might be waded through, still even that is made impossible on account of the smaller ditches mentioned under No. 2, which are not visible. It is only where these ditches have a corresponding direction, so that we can move between two of them without crossing either, that the inundation does not constitute in effect an absolute bar to all communication. It is easy to conceive that this exception to the general obstruction can only be for short distances, and, therefore, can only be used for tactical purposes of an entirely special character.

From all this we deduce

1. That the assailant’s means of moving are limited to a more or less small number of practicable lines, which run along very narrow dykes, and usually have a wet ditch on the right and left, consequently form very long defiles.

2. That every defensive preparation upon such a dam may be easily strengthened to such a degree as to become impregnable.

3. But that, because the defensive is so hemmed in, he must confine himself to the most passive resistance as respects each isolated point, and consequently must look for his safety entirely from passive resistance.

4. That in such a country it is not a system of a single defensive line, closing the country like a simple barrier, but that as in every direction the same obstacle to movement exists, and the same security for flanks may be found, new posts may incessantly be formed, and in this manner any portion of the first defensive line, if lost, may be replaced by a new piece. We may say that the number of combinations here, like those on a chessboard, are infinite.

5. But while this general condition of a country is only conceivable along with the supposition of a high degree of cultivation and a dense population, it follows of itself that the number of passages, and therefore the number of posts required or their defence, must be very great in comparison to other strategetic dispositions; from which again we have, as a consequence, that such a defensive line must not be long.

The principal line of defence in Holland is from Naarden on the Zuyder Zee (the greater part of the way behind the Vecht), to Gorcum on the Waal, that is properly to the Biesbosch, its extent being about eight miles. For the defence of this line a force of 25,000 to 30,000 was employed in 1672, and again in 1787. If we could reckon with certainty upon an invincible resistance, the results would certainly be very great, at least for the provinces of Holland lying behind that line.

In 1672 the line actually withstood very superior forces led by great generals, first Condé, and afterwards Luxembourg, who had under their command 40,000 to 50,000 men, and yet would not assault, preferring to wait for the winter, which did not prove severe enough. On the other hand, the resistance which was made on this first line in 1787 amounted to nothing, and even that which was made by a second line much shorter, between the Zuyder Zee and the lake of Haarlem, although somewhat more effective, was overcome by the Duke of Brunswick in one day, through a very skilful tactical disposition well adapted to the locality, and this although the Prussian force actually engaged in the attack was little, if at all, superior in numbers to the troops guarding the lines.

The different result in the two cases is to be attributed to the difference in the supreme command. In the year 1672 the Dutch were surprised by Louis XIV., while everything was on a peace establishment, in which, as is well known, there breathed very little military spirit as far as concerned land forces. For that reason the greater number of the fortresses were deficient in all articles of material and equipment, garrisoned only by weak bodies of hired troops, and defended by governors who were either native-born incapables, or treacherous foreigners. Thus all the Brandenburg fortresses on the Rhine, garrisoned by Dutch, as well as all their own places situated to the east of the line of defence above described, except Groningen, very soon fell into the hands of the French, and for the most part without any real defence. And in the conquest of this great number of places consisted the chief exertions of the French army, 150,000 strong, at that time.

But when, after the murder of the brothers De Witt, in August 1672, the Prince of Orange came to the head of affairs, bringing unity to the measures for national defence, there was still time to close the defensive line above-mentioned, and all the measures then adopted harmonised so well with each other that neither Condé nor Luxembourg, who commanded the French armies left in Holland after the departure of the two armies under Turenne and Louis in person, would venture to attempt anything against the separate posts.

In the year 1787 all was different. It was not the Republic of seven united provinces, but only the province of Holland which had to resist the invasion. The conquest of all the fortresses, which had been the principal object in 1672, was therefore not the question; the defence was confined at once to the line we have described. But the assailant this time, instead of 150,000 men, had only 25,000, and was no mighty sovereign of a great country adjoining Holland, but the subordinate general of a distant prince, himself by no means independent in many respects. The people in Holland, like those everywhere else at that time, were divided into two parties, but the republican spirit in Holland was decidedly predominant, and had at the same time attained even to a kind of enthusiastic excitement. Under these circumstances the resistance in the year 1787 ought to have ensured at least as great results as that of 1672. But there was one important difference, which is, that in the year 1787 unity of command was entirely wanting. What in 1672 had been left to the wise, skilful, and energetic guidance of the Prince of Orange, was entrusted to a so called Defence Commission in 1787, which although it included in its number men of energy, was not in a position to infuse into its work the requisite unity of measures, and to inspire others with that confidence which was wanted to prevent the whole instrument from proving imperfect and inefficient in use.

We have dwelt for a moment on this example, in order to give more distinctness to the conception of this defensive measure, and at the same time to show the difference in the effects produced, according as more or less unity and sequence prevail in the direction of the whole.

Although the organisation and method of defence of such a defensive line are tactical subjects, still, in connection with the latter, which is the nearest allied to strategy, we cannot omit to make an observation to which the campaign of 1787 gives occasion.

We think, namely, that however passive the defence must naturally be at each point in a line of this kind, still an offensive action from some one point of the line is not impossible, and may not be unproductive of good results if the enemy, as was the case in 1787, is not decidedly very superior. For although such an attack must be executed by means of dykes, and on that account cannot certainly have the advantage of much freedom of movement or of any great impulsive force, nevertheless, it is impossible for the offensive side to occupy all the dykes and roads which he does not require for his own purposes, and therefore the defensive with his better knowledge of the country, and being in possession of the strong points, should be able by some of the unoccupied dykes to effect a real flank attack against the columns of the assailant, or to cut them off from their sources of supply. If now, on the other hand, we reflect for a moment on the constrained position in which the assailant is placed, how much more dependent he is on his communications than in almost any other conceivable case, we may well imagine that every sally on the part of the defensive side which has the remotest possibility of success must at once as a demonstration be most effective. We doubt very much if the prudent and cautious duke of Brunswick would have ventured to approach Amsterdam if the Dutch had only made such a demonstration, from Utrecht for instance.

XXI. Defence of Forests

Above all things we must distinguish thick tangled and impassable forests from extensive woods under a certain degree of culture, which are partly quite clear, partly intersected by numerous roads.

Whenever the object is to form a defensive line, the latter should be left in rear or avoided as much as possible. The defensive requires more than the assailant to see clearly round him, partly because, as a rule, he is the weaker, partly because the natural advantages of his position cause him to develop his plans later than the assailant. If he should place a woody district before him he would be fighting like a blind man against one with his eyesight. If he should place himself in the middle of the wood then both would be blind, but that equality of condition is just what would not answer the natural requirements of the defender.

Such a wooded country can therefore not be brought into any favourable connection with the defensive except it is kept in rear of the defender’s army, so as to conceal from the enemy all that takes place behind that army, and at the same time to be available as an assistance to cover and facilitate the retreat.

At present we only speak of forests in level country, for where the decided mountain character enters into combination, its influence becomes predominant over tactical and strategic measures, and we have already treated of those subjects elsewhere.

But impassable forests, that is, such as can only be traversed on certain roads, afford advantages in an indirect defence similar to those which the defence derives from mountains for bringing on a battle under favourable circumstances; the army can await the enemy behind the wood in a more or less concentrated position with a view to falling on him the moment he debouches from the road defiles. Such a forest resembles mountain in its effects more than a river: for it affords, it is true, only one very long and difficult defile, but it is in respect to the retreat rather advantageous than otherwise.

But a direct defence of forests, let them be ever so impracticable, is a very hazardous piece of work for even the thinnest chain of outposts; for abattis are only imaginary barriers, and no wood is so completely impassable that it cannot be penetrated in a hundred places by small detachments, and these, in their relation to a chain of defensive posts, may be likened to the first drops of water which ooze through a roof and are soon followed by a general rush of water.

Much more important is the influence of great forests of every kind in connection with the arming of a nation; they are undoubtedly the true element for such levies; if, therefore, the strategic plan of defence can be so arranged that the enemy’s communications pass through great forests, then, by that means, another mighty lever is brought into use in support of the work of defence.

XX. The Cordon

The term cordon is used to denote every defensive plan which is intended directly to cover a whole district of country by a line of posts in connection with each other. We say directly, for several corps of a great army posted in line with each other might protect a large district of country from invasion without forming a cordon; but then this protection would not be direct, but through the effect of combinations and movements.

It is evident at a glance that such a long defensive line as that must be, which is to cover an extensive district of country directly, can only have a very small degree of defensive stamina. Even when very large bodies of troops occupy the lines this would be the case if they were attacked by corresponding masses. The object of a cordon can therefore only be to resist a weak blow, whether that the weakness proceeds from a feeble will or the smallness of the force employed.

With this view the wall of China was built: a protection against the inroads of Tartars. This is the intention of all lines and frontier defences of the European States bordering on Asia and Turkey. Applied in this way the cordon system is neither absurd nor does it appear unsuitable to its purpose. Certainly it is not sufficient to stop all inroads, but it will make them more difficult and therefore of less frequent occurrence, and this is a point of considerable importance where relations subsist with people like those of Asia, whose passions and habits have a perpetual tendency to war.

Next to this class of cordons come the lines, which, in the wars of modern times have been formed between European States, such as the French lines on the Rhine and in the Netherlands. These were originally formed only with a view to protect a country against inroads made for the purpose of levying contributions or living at the expense of the enemy. They are, therefore, only intended to check minor operations, and consequently it is also meant that they should be defended by small bodies of troops. But, of course, in the event of the enemy’s principal force taking its direction against these lines, the defender must also use his principal force in their defence, an event by no means conducive to the best defensive arrangements. On account of this disadvantage and because the protection against incursions in temporary war is quite a minor object, by which through the very existence of these lines an excessive expenditure of troops may easily be caused, their formation is looked upon in our day as a pernicious measure. The more power and energy thrown into the prosecution of the war the more useless and dangerous this means becomes.

Lastly, all very extended lines of outposts covering the quarters of an army and intended to offer a certain amount of resistance come under the head of cordons.

This defensive measure is chiefly designed as an impediment to raids, and other such minor expeditions directed against single cantonments, and for this purpose it may be quite sufficient if favoured by the country. Against an advance of the main body of the enemy the opposition offered can be only relative, that is, intended to gain time: but as this gain of time will be but inconsiderable in most cases, this object may be regarded as a very minor consideration in the establishment of these lines. The assembling and advance of the enemy’s army itself can never take place so unobservedly that the defender gets his first information of it through his outposts; when such is the case he is much to be pitied.

Consequently, in this case also, the cordon is only intended to resist the attack of a weak force, and the object, therefore, in this and in the other two cases is not at variance with the means.

But that an army formed for the defence of a country should spread itself out in a long line of defensive posts opposite to the enemy, that it should disperse itself in a cordon form, seems to be so absurd that we must seek to discover the circumstances and motives which lead to and accompany such a proceeding.

Every position in a mountainous country, even if taken up with the view of a battle with the whole force united, is and must necessarily be more extended than a position in a level country. It may be because the aid of the ground augments very much the force of the resistance; it must be because a wider basis of retreat is required, as we have shown in the chapter on mountain defences. But if there is no near prospect of a battle, if it is probable that the enemy will remain in his position opposite to us for some time without undertaking anything unless tempted by some very favourable opportunity which may present itself (the usual state of things in most wars formerly), then it is also natural not to limit ourselves merely to the occupation of so much country as is absolutely necessary, but to hold as much right or left as is consistent with the security of the army, by which we obtain many advantages, as we shall presently show. In open countries with plenty of communications, this object may be effected to a greater extent than in mountains, through the principle of movement, and for that reason the extension and dispersion of the troops is less necessary in an open country; it would also be much more dangerous there on account of the inferior capability of resistance of each part.

But in mountains where all occupation of ground is more dependent on local defence, where relief cannot so soon be afforded to a point menaced, and where, when once the enemy has got possession of a point, it is more difficult to dislodge him by a force slightly superior—in mountains, under these circumstances, we shall always come to a form of position which, if not strictly speaking a cordon, still approaches very near to it, being a line of defensive posts. From such a disposition, consisting of several detached posts, to the cordon system, there is still certainly a considerable step, but it is one which generals, nevertheless, often take without being aware of it, being drawn on from one step to another. First, the covering and the possession of the country is the object of the dispersion; afterwards it is the security of the army itself. Every commander of a post calculates the advantage which may be derived from this or that point connected with the approach to his position on the right or the left, and thus the whole progresses insensibly from one degree of subdivision to another.

A cordon war, therefore, carried on by the principal force of an army, is not to be considered a form of war designedly chosen with a view to stopping every blow which the enemy’s forces might attempt, but a situation which the army is drawn into in the pursuit of a very different object, namely, the holding and covering the country against an enemy who has no decisive undertaking in view. Such a situation must always be looked upon as a mistake; and the motives through which generals have been lured by degrees into allowing one small post after another, are contemptible in connection with the object of a large army; this point of view shows, at all events, the possibility of such a mistake. That it is really an error, namely, a mistaken appreciation of our own position, and that of the enemy is sometimes not observed, and it is spoken of as an erroneous system. But this same system, when it is pursued with advantage, or, at all events, without causing damage, is quietly approved. Every one praises the faultless campaigns of Prince Henry in the Seven Years’ War, because they have been pronounced so by the king, although these campaigns exhibit the most decided and most incomprehensible examples of chains of posts so extended that they may just with as much propriety be called cordons as any that ever were. We may completely justify these positions by saying, the prince knew his opponent; he knew that he had no enterprises of a decisive character to apprehend from that quarter, and as the object of his position besides was to occupy always as much territory as possible, he therefore carried out that object as far as circumstances in any way permitted. If the prince had once been unfortunate with one of these cobwebs, and had met with a severe loss, we should not say that he had pursued a faulty system of warfare, but that he had been mistaken about a measure and had applied it to a case to which it was not suited.

While we thus seek to explain how the cordon system, as it is called, may be resorted to by the principal force in a theatre in war, and how it may even be a judicious and useful measure, and, therefore, far from being an absurdity, we must, at the same time, acknowledge that there appear to have been instances where generals or their staff have overlooked the real meaning or object of a cordon system, and assumed its relative value to be a general one; conceiving it to be really suited to afford protection against every kind of attack, instances, therefore, where there was no mistaken application of the measure but a complete misunderstanding of its nature; we shall further allow that this very absurdity amongst others seems to have taken place in the defence of the Vosges by the Austrian and Prussian armies in 1793 and 1794.

XXIII. Key to the Country

There is no theoretical idea in the art of war which has played such a part in criticism as that we are now entering upon. It is the “great war steed” in all accounts of battles and campaigns; the most frequent point of view in all arguments, and one of those fragments of scientific form with which critics make a show of learning. And yet the conception embodied in it has never yet been established, nor has it ever been clearly explained.

We shall try to ascertain its real meaning, and then see how far it can be made available for practical use.

We treat of it here because the defence of mountains, river defences, as well as the conceptions of strong and entrenched camps with which it closely connects itself, required to have precedence.

The indefinite confused conception which is concealed behind this ancient military metaphor has sometimes signified the most exposed part of a country at other times the strongest.

If there is any spot without the possession of which no one dare venture to penetrate into an enemy’s country that may, with propriety, be called the key of that country. But this simple, though certainly at the same time also, barren notion has not satisfied theorists, and they have amplified it, and under the term key of a country imagined points which decide upon the possession of the whole country.

When the Russians wanted to advance into the Crimean peninsula, they were obliged to make themselves masters of the isthmus of Perekop and its lines, not so much to gain an entrance generally—for Lascy turned it twice (1737 and 1738)—but to be able to establish themselves with tolerable security in the Crimea. That is very simple, but we gain very little in this through the conception of a key-point. But if it might be said, Whoever has possession of the district of Langres commands all France as far as Paris—that is to say, it only rests with himself to take possession—that is plainly a very different thing, something of much higher importance. According to the first kind of conception the possession of the country cannot be thought of without the possession of the point which we have called key; that is a thing which is intelligible to the most ordinary capacity: but according to the second kind of conception, the possession of the point which we have called key, cannot be imagined without the possession of the country following as a necessary consequence; that is plainly, something marvellous, common sense is no longer sufficient to grasp this, the magic of the occult sciences must be called into requisition. This cabala came into existence in works published fifty years ago, and reached its zenith at the end of the last century; and notwithstanding the irresistible force, certainty and distinctness with which Buonaparte’s method of conducting war carried conviction generally, this cabala has, nevertheless, still managed, we say, to spin out the thread of its tenacious existence through the medium of books.

(Setting aside for a moment our conception of the key-point) it is self-evident that in every country there are points of commanding importance, where several roads meet, where our means of subsistence may be conveniently collected, which have the advantage of being centrally situated with reference to other important points, the possession of which in short meets many requirements and affords many advantages. Now, if generals wishing to express the importance of such a point by one word have called it the key of the land, it would be pedantic affectation to take offence at their using that term; on the contrary we should rather say the term is very expressive and pleasing. But if we try to convert this mere flower of speech into the germ of a system branching out like a tree into many ramifications, common sense rises in opposition, and demands that the expression should be restricted to its true value.

In order to develop a system out of the expression, it was necessary to resort to something more distinct and absolute than the practical, but certainly very indefinite, meaning attaching to the term in the narrations of generals when speaking of their military enterprises. And from amongst all its various relations, that of high ground was chosen.

Where a road traverses a mountain ridge, we thank heaven when we get to the top and have only to descend. This feeling so natural to a single traveller is still more so in the case of an army All difficulties seem to be overcome, and so they are indeed in most instances; we find that the descent is easy, and we are conscious of a kind of feeling of superiority over any one who would stop us; we have an extensive view over the country, and command it with a look beforehand. Thus the highest point on a road over a mountain is always considered to possess a decisive importance, and it does in fact in the majority of cases, but by no means in all. Such points are very often described in the despatches of generals by the name of key-points; but certainly again in a somewhat different and generally in a more restricted sense. This idea has been the starting point of a false theory (of which, perhaps, Lloyd may be regarded as the founder); and on this account, elevated points from which several roads descend into the adjacent country, came to be regarded as the keypoints of the country—as points which command the country. It was natural that this view should amalgamate itself with one very nearly connected with it, that of a systematic defence of mountains, and that the matter should thus be driven still further into the regions of the illusory; added to which many tactical elements connected with the defence of mountains came into play, and thus the idea of the highest point in the road was soon abandoned, and the highest point generally of the whole mountain system, that is the point of the watershed, was substituted for it as the key of the country.

Now just at that time, that is the latter half of the preceding century, more definite ideas on the forms given to the surface of the earth through aqueous action became current; thus natural science lent a hand to the theory of war by this geological system, and then every barrier of practical truth was broken through, and reasoning floated in the illusory system of a geological analogy. In consequence of this, about the end of the eighteenth century we heard, or rather we read, of nothing but the sources of the Rhine and Danube. It is true that this nuisance prevailed mostly in books, for only a small portion of book wisdom ever reaches the real world, and the more foolish a theory the less it will attain to practice; but this of which we are now speaking has not been unproductive of injury to Germany by its practical effects, therefore we are not fighting with a windmill, in proof of which we shall quote two examples; first, the important but very scientific campaigns of the Prussian army, 1793 and 1794 in the Vosges, the theoretical key to which will be found in the works of Gravert and Massenbach; secondly, the campaign of 1814, when, on the principle of the same theory, an army of 200,000 men was led by the nose through Switzerland on to the plateau of Langres as it is called.

But a high point in a country from which all its waters flow, is generally nothing more than a high point; and all that in exaggeration and false application of ideas, true in themselves, was written at the end of the eighteenth and commencement of the nineteenth centuries, about its influence on military events, is completely imaginary. If the Rhine and Danube and all the six rivers of Germany had their common source on the top of one mountain, that mountain would not on that account have any claim to any greater military value than being suited for the position of a trigonometrical point. For a signal tower it would be less useful, still less so for a vidette, and for a whole army worth just nothing at all.

To seek for a key-position therefore in the so called key country, that is where the different branches of the mountains diverge from a common point, and at the highest source of its waters, is merely an idea in books, which is overthrown by nature itself, because nature does not make the ridges and valleys so easy to descend as is assumed by the hitherto so called theory of ground, but distributes peaks and gorges, in the most irregular manner, and not unfrequently the lowest water level is surrounded by the loftiest masses of mountain. If any one questions military history on the subject, he will soon convince himself that the leading geological points of a country exercise very little regular influence on the use of the country for the purposes of war, and that little is so over-balanced by other local circumstances, and other requirements, that a line of positions may often run quite close to one of the points we are discussing without having been in any way attracted there by that point.

We have only dwelt so long upon this false idea because a whole—and very pretentious—system has built itself upon it. We now leave it, and turn back to our own views.

We say, then, that if the expression, key-position, is to represent an independent conception in strategy, it must only be that of a locality the possession of which is indispensable before daring to enter the enemy’s country. But if we choose to designate by that term every convenient point of entrance to a country, or every advantageous central point in the country, then the term loses its real meaning (that is, its value), and denotes something which may be found anywhere more or less. It then becomes a mere pleasing figure of speech.

But positions such as the term conveys to our mind are very rarely indeed to be found. In general, the best key to the country lies in the enemy’s army; and when the idea of country predominates over that of the armed force, some very specially advantageous circumstances must prevail. These, according to our opinion, may be recognised by their tending to two principal results: first, that the force occupying the position, through the help of the ground, obtains extraordinary capability of tactical resistance; second, that the enemy’s lines of communication can be sooner effectively threatened from this position than he can threaten ours.

XXIV. Operating Against a Flank

We need hardly observe that we speak of the strategic flank, that is, a side of the theatre of war, and that the attack from one side in battle, or the tactical movement against a flank, must not be confounded with it; and even in cases in which the strategic operation against a flank, in its last stage, ends in the tactical operation, they can quite easily be kept separate, because the one never follows necessarily out of the other.

These flanking movements, and the flanking positions connected with them, belong also to the mere useless pageantry of theory, which is seldom met with in actual war. Not that the means itself is either ineffectual or illusory, but because both sides generally seek to guard themselves against its effects; and cases in which this is impossible are rare. Now in these uncommon cases this means has often also proved highly efficacious, and for this reason, as well as on account of the constant watching against it which is required in war, it is important that it should be clearly explained in theory. Although the strategic operation against a flank can naturally be imagined, not only on the part of the defensive, but also on that of the offensive, still it has much more affinity with the first, and therefore finds its place under the head of defensive means.

Before we enter into the subject, we must establish the simple principle, which must never be lost sight of afterwards in the consideration of the subject, that troops which are to act against the rear or flank of the enemy cannot be employed against his front, and that, therefore, whether it be in tactics or strategy, it is a completely false kind of notion to consider that coming on the rear of the enemy is at once an advantage in itself. In itself, it is as yet nothing; but it will become something in connection with other things, and something either advantageous or the reverse, according to the nature of these things, the examination of which now claims our attention.

First, in the action against the strategic flank, we must make a distinction between two objects of that measure—between the action merely against the communications, and that against the line of retreat, with which, at the same time, an effect upon the communications may also be combined.

When Daun, in 1758, sent a detachment to seize the convoys on their way to the siege of Olmütz, he had plainly no intention of impeding the king’s retreat into Silesia; he rather wished to bring about that retreat, and would willingly have opened the line to him.

In the campaign of 1812, the object of all the expeditionary corps that were detached from the Russian army in the months of September and October, was only to intercept the communications, not to stop the retreat; but the latter was quite plainly the design of the Moldavian army which, under Tschitschagof, marched against the Beresina, as well as of the attack which General Wittgenstein was commissioned to make on the French corps stationed on the Dwina.

These examples are merely to make the exposition clearer.

The action against the lines of communication is directed against the enemy’s convoys, against small detachments following in rear of the army, against couriers and travellers, small depôts, etc.; in fact, against all the means which the enemy requires to keep his army in a vigorous and healthy condition; its object is, therefore, to weaken the condition of the enemy in this respect, and by this means to cause him to retreat.

The action against the enemy’s line of retreat is to cut his army off from that line. It cannot effect this object unless the enemy really determines to retreat; but it may certainly cause him to do so by threatening his line of retreat, and, therefore, it may have the same effect as the action against the line of communication, by working as a demonstration. But as already said, none of these effects are to be expected from the mere turning which has been effected, from the mere geometrical form given to the disposition of the troops, they only result from the conditions suitable to the same.

In order to learn more distinctly these conditions, we shall separate completely the two actions against the flank, and first consider that which is directed against the communications.

Here we must first establish two principal conditions, one or other of which must always be forthcoming.

The first is, that the forces used for this action against the flank of the enemy must be so insignificant in numbers that their absence is not observed in front.

The second, that the enemy’s army has run its career, and therefore can neither make use of a fresh victory over our army, nor can he pursue us if we evade a combat by moving out of the way.

This last case, which is by no means so uncommon as might be supposed, we shall lay aside for the moment, and occupy ourselves with the accessory conditions of the first.

The first of these is, that the communications have a certain length, and cannot be protected by a few good posts; the second point is, that the situation of the line is such as exposes it to our action.

This weakness of the line may arise in two ways—either by its direction, if it is not perpendicular to the strategic front of the enemy’s army, or because his lines of communication pass through our territory; if both these circumstances exist, the line is so much the more exposed. These two relations require a closer examination.

One would think that when it is a question of covering a line of communication forty or fifty miles long, it is of little consequence whether the position occupied by an army standing at one extremity of this line forms an oblique angle or a right angle in reference to it, as the breadth of the position is little more than a mere point in comparison to the line; and yet it is not so unimportant as it may seem. When an army is posted at a right angle with its communications, it is difficult, even with a considerable superiority, to interrupt the communications by any detachments or partisans sent out for the purpose. If we think only of the difficulty of covering absolutely a certain space, we should not believe this, but rather suppose, on the contrary, that it must be very difficult for an army to protect its rear (that is, the country behind it) against all expeditions which an enemy superior in numbers may undertake. Certainly, if we could look at everything in war as it is on a sheet of paper! Then the party covering the line, in his uncertainty as to the point where light troops or partisans may appear, would be in a certain measure blind, and only the partisans would see. But if we think of the uncertainty and insufficiency of intelligence gained in war, and know that both parties are incessantly groping in the dark, then we easily perceive that a detached corps sent round the enemy’s flank to gain his rear is in the position of a man engaged in a fray with numbers in a dark room. In the end he must fall; and so must it also be with bands who get round an army occupying a perpendicular position, and who therefore place themselves near to the enemy, but widely separated from their own people. Not only is there danger of losing numbers in this way; there is also a risk of the whole instrument itself being blunted immediately; for the very first misfortune which happens to one such party will make all the others timid, and instead of bold attacks and insolent dodging, the only play will be constant running away.

Through this difficulty, therefore, an army occupying a perpendicular position covers the nearest points on its line of communications for a distance of two or three marches, according to the strength of the army; but those nearest points are just those which are most in danger, as they are the nearest to the enemy.

On the other hand, in the case of a decidedly oblique position, no such part of the line of communication is covered; the smallest pressure, the most insignificant attempt on the part of the enemy, leads at once to a vulnerable point.

But now, what is it which determines the front of a position, if it is not just the direction perpendicular to the line of communication? The front of the enemy; but then, again, this may be equally as well supposed as dependent on our front. Here there is a reciprocal effect, for the origin of which we must search.

If we suppose the lines of communication of the assailant, a b, so situated with respect to those of the enemy, c d, that the two lines form a considerable angle with each other, it is evident that if the defensive wishes to take up a position at e, where the two lines intersect, the assailant from b, by the mere geometrical relation, could compel him to form front opposite to him, and thus to lay bare his communications. The case would be reversed if the defensive took up his position on this side of the point of junction, about d; then the assailant must make front towards him, if so be that his line of operations, which closely depends on geographical conditions, cannot be arbitrarily changed, and moved, for instance, to the direction a d. From this it would seem to follow that the defender has an advantage in this system of reciprocal action, because he only requires to take a position on this side of the intersection of the two lines. But very far from attaching any importance to this geometrical element, we only brought it into consideration to make ourselves the better understood; and we are rather of opinion that local and generally individual relations have much more to do with determining the position of the defender; that, therefore, it is quite impossible to lay down in general which of two belligerents will be obliged soonest to expose his communications.

If the lines of communication of both sides lie in one and the same direction, then whichever of the two parties takes up an oblique position will certainly compel his adversary to do the same. But then there is nothing gained geometrically by this, and both parties attain the same advantages and disadvantages.

In the continuation of our considerations we shall, therefore, confine ourselves to the case of the line of communication of one side only being exposed.

Now as regards the second disadvantageous relation of a line of communication, that is to say, when it runs through an enemy’s country, it is clear in itself how much the line is compromised by that circumstance, if the inhabitants of the country have taken up arms; and consequently the case must be looked at as if a body of the enemy was posted all along the line; this body, it is true, is in itself weak without solidity or intensive force; but we must also take into consideration what the close contact and influence of such a hostile force may nevertheless effect through the number of points which offer themselves one after another on long lines of communication. That requires no further explanation. But even if the enemy’s subjects have not taken up arms, and even if there is no militia in the country, or other military organisation, indeed if the people are even very unwarlike in spirit, still the mere relation of the people as subjects to a hostile government is a disadvantage for the lines of communication of the other side which is always felt. The assistance which expeditionary forces and partisans derive merely through a better understanding with the people, through a knowledge of the country and its inhabitants, through good information, through the support of official functionaries, is, for them, of decided value; and this support every such body will enjoy without any special effort on its own part. Added to this, within a certain distance there will not be wanting fortresses, rivers, mountains, or other places of refuge, which of ordinary right belong to the enemy, if they have not been formally taken possession of and occupied by our troops.

Now in such a case as is here supposed, especially if attended with other favourable circumstances, it is possible to act against the communications of an army, although their direction is perpendicular to the position of that army; for the detachments employed for the purpose do not then require to fall back always on their own army, because being in their own country they are safe enough if they only make their escape.

We have, therefore, now ascertained that—

1. A considerable length,

2. An oblique direction,

3. An enemy’s province,

are the principal circumstances under which the lines of communication of an army may be interrupted by a relatively small proportion of armed forces on the side of the enemy; in order to make this interruption effectual, a fourth condition is still requisite, which is a certain duration of time. Respecting this point, we beg attention to what has been said in the fifteenth chapter of the fifth book.

But these four conditions are only the chief points which relate to the subject; a number of local and special circumstances attach themselves to these, and often attain to an influence more decisive and important than that of the principal ones themselves. Selecting only the most essential, we mention the state of the roads, the nature of the country through which they pass, the means of cover which are afforded by rivers, mountains, and morasses, the seasons and weather, the importance of particular convoys, such as siege trains, the number of light troops, etc., etc.

On all these circumstances, therefore, will depend the effect with which a general can act on his opponent’s communications; and by comparing the result of the whole of these circumstances on the one side with the result of the whole on the other, we obtain a just estimate of the relative advantages of both systems of communication, on which will depend which of the two generals can play the highest game.

What here seems so prolix in the explanation is often decided in the concrete case at first sight; but still, the tact of a practised judgment is required for that, and person must have thought over every one of the cases now developed in order to see in its true light the absurdity of those critical writers who think they have settled something by the mere words “turning” and “acting on a flank,” without giving their reasons.

We now come to the second chief condition, under which the strategic action against the enemy’s flank may take place.

If the enemy is hindered from advancing by any other cause but the resistance which our army opposes, let that cause be what it may, then our army has no reason to be apprehensive about weakening itself by sending out detachments to harass the enemy; for if the enemy should attempt to chastise us by an attack, we have only to yield some ground and decline the combat. This is what was done by the chief Russian army at Moscow in 1812. But it is not at all necessary that everything should be again on the same great scale as in that campaign for such a case to happen again. In the first Silesian war, Frederick the Great was each time in this situation, on the frontiers of Bohemia and Moravia, and in the complex affairs relating to generals and their armies, many causes of different kinds, particularly political ones, may be imagined, which make further advance an impossibility.

As in the case now supposed more forces may be spared to act against the enemy’s flank, the other conditions need not be quite so favourable: even the nature of our communications in relation to those of the enemy need not give us the advantage in that respect, as an enemy who is not in a condition to make any particular use of our further retreat is not likely to use his right to retaliate, but will rather be anxious about the direct covering of his own line of retreat.

Such a situation is therefore very well suited to obtain for us, by means less brilliant and complete but less dangerous than a victory, those results which it would be too great a risk to seek to obtain by a battle.

As in such a case we feel little anxiety about exposing our own line of communications, by taking up a position on one or other flank, and as the enemy by that means may always be comspelled to form front obliquely to his line of communications, therefore this one of the conditions above named will seldom fail to occur. The more the rest of the conditions, as well as other circumstances, co-operate, so much the more certain are we of success from the means now in question; but the fewer favourable circumstances exist, the more will all depend on superior skill in combination, and promptitude and precision in the execution.

Here is the proper field for strategic manœuvres, such as are to be found so frequently in the Seven Years’ War, in Silesia and Saxony, and in the campaigns of 1760 and 1762. If, in many wars in which only a moderate amount of elementary force is displayed, such strategic manœuvring very often appears, this is not because the commander on each occasion found himself at the end of his career, but because want of resolution and courage, and of an enterprising spirit, and dread of responsibility, have often supplied the place of real impediments; for a case in point, we have only to call to mind Field Marshal Daun.

As a summary of the results of our considerations, we may say, that the action against a flank is most effectual—

1. In the defensive;

2. Towards the end of a campaign;

3. Above all, in a retreat into the heart of the country; and

4. In connection with a general arming of the people.

On the mode of executing this action against the communications, we have only a few words to say.

The enterprises must be conducted by skilful detachment leaders, who, at the head of small bodies, by bold marches and attacks, fall upon the enemy’s weak garrisons, convoys, and small detachments on the march here and there, encourage the national levies (landsturm), and sometimes join with them in particular undertakings. These parties must be more numerous than strong individually, and so organised that it may be possible to unite several of them for any greater undertaking without any obstacle from the vanity or caprice of any of the single leaders.

We have now to speak of the action against the enemy’s line of retreat.

Here we must keep in view, above all things, the principle with which we commenced, that forces destined to operate in rear cannot be used in front; that, therefore, the action against the rear or flanks is not an increase of force in itself; it is only to be regarded as a more powerful application (or employment) of the same; increasing the degree of success in prospect, but also increasing the degree of risk.

Every opposition offered with the sword which is not of a direct and simple nature, has a tendency to raise the result at the cost of its certainty. An operation against the enemy’s flank, whether with one compact force, or with separate bodies converging from several quarters, belongs to this category.

But now, if cutting off the enemy’s retreat is not to be a mere demonstration, but is seriously intended, the real solution is a decisive battle, or, at least, the conjunction of all the conditions for the same; and just in this solution we find again the two elements above-mentioned—the greater result and the greater danger. Therefore, if a general is to stand justified in adopting this method of action, his reasons must be favourable conditions.

In this method of resistance we must distinguish the two forms already mentioned. The first is, if a general with his whole force intends to attack the enemy in rear, either from a position taken up on the flank for that purpose, or by a formal turning movement; the second is, if he divides his forces, and, by an enveloping position with one part, threatens the enemy’s rear, with the other part his front.

The result is intensified in both cases alike, that is—either there is a real interception of the retreat, and consequently the enemy’s army taken prisoners, or the greater part scattered, or there may be a long and hasty retreat of the enemy’s force to escape the danger.

But the intensified risk is different in the two cases.

If we turn the enemy with our whole force, the danger lies in the laying open our own rear; and hence the question again depends on the relation of the mutual lines of retreat, just as in the action against the lines of communication, it depended on the relation of those lines.

Now certainly the defender, if he is in his own country, is less restricted than the assailant, both as to his lines of retreat and communication, and in so far is therefore in a better position to turn his adversary strategically; but this general relation is not of a sufficiently decisive character to be used as the foundation of a practical method; therefore, nothing but the whole of the relations in each individual case can decide.

Only so much we may add, that favourable conditions are naturally more common in wide spheres of action than in small; more common, also, on the side of independent states than on that of weak ones, dependent on foreign aid, and whose armies must, therefore, constantly have their attention bent on the point of junction with the auxiliary army; lastly, they become most favorable for the defender towards the close of the campaign, when the impulsive force of the assailant is somewhat spent; very much, again, in the same manner as in the case of the lines of communication.

Such a flank position as the Russians took up with such advantage on the road from Moscow to Kaluga, when Buonaparte’s aggressive force was spent, would have brought them into a scrape at the commencement of the campaign at the camp of Drissa, if they had not been wise enough to change their plan in good time.

The other method of turning the enemy, and cutting off his retreat by dividing our force, entails the risk attending a division of our own force, whilst the enemy, having the advantage of interior lines, retains his forces united, and therefore has the power of acting with superior numbers against one of our divisions. This is a disadvantage which nothing can remove, and in exposing ourselves to it, we can only be justified by one of three principal reasons:—

1. The original division of the force which makes such a method of action necessary, unless we incur a great loss of time.

2. A great moral and physical superiority, which justifies the adoption of a decisive method.

3. The want of impulsive force in the enemy as soon as he has arrived at the culminating point of his career.

When Frederick the Great invaded Bohemia, 1757, on converging lines, he had not in view to combine an attack in front with one on the strategic rear, at all events, this was by no means his principal object, as we shall more fully explain elsewhere, but in any case it is evident that there never could have been any question of a concentration of forces in Silesia or Saxony before the invasion, as he would thereby have sacrificed all the advantages of a surprise.

When the allies formed their plan for the second part of the campaign of 1813, looking to their great superiority in numbers, they might very well at that time entertain the idea of attacking Buonaparte’s right on the Elbe with their main force, and of thus shifting the theatre of war from the Oder to the Elbe. Their ill-success at Dresden is to be ascribed not to this general plan but to their faulty dispositions both strategic and tactical. They could have concentrated 220,000 men at Dresden against Buonaparte’s 130,000, a proportion of numbers eminently favourable (at Leipsic, at least, the proportion was as 285 : 157). It is true that Buonaparte had distributed his forces too evenly for the particular system of a defence upon one line (in Silesia 70,000 against 90,000, in the Mark—Brandenburg—70,000 against 110,000), but at all events it would have been difficult for him, without completely abandoning Silesia, to assemble on the Elbe a force which could have contended with the principal army of the allies in a decisive battle. The allies could also have easily called up the army of Wrede to the Maine, and employed it to try to cut Buonaparte off from the road to Mayence.

Lastly, in 1812, the Russians might have directed their army of Moldavia upon Volhynia and Lithuania in order to move it forward afterwards against the rear of the principal French army, because it was quite certain that Moscow must be the extreme point of the French line of operations. For any part of Russia beyond Moscow there was nothing to fear in that campaign, therefore the Russian main army had no cause to consider itself too weak.

This same scheme formed part of the disposition of the forces laid down in the first defensive plan proposed by General Phul, according to which the army of Barclay was to occupy the camp at Drissa, whilst that under Bragathion was to press forward against the rear of the main French army. But what a difference of circumstances in the two cases! In the first of them the French were three times as strong as the Russians; in the second, the Russians were decidedly superior. In the first, Buonaparte’s great army had in it an impulsive force which carried it to Moscow 80 miles beyond Drissa: in the second, it is unfit to make a day’s march beyond Moscow; in the first, the line of retreat on the Niemen did not exceed 30 miles: in the second it was 112. The same action against the enemy’s retreat therefore, which was so successful in the second case, would, in the first, have been the wildest folly.

As the action against the enemy’s line of retreat, if it is more than a demonstration, becomes a formal attack from the rear, there remains therefore still a good deal to be said on the subject, but it will come in more appropriately in the book upon the attack; we shall therefore break off here and content ourselves with having given the conditions under which this kind of reaction may take place.

Very commonly the design of causing the enemy to retreat by menacing his line of retreat, is understood to imply rather a mere demonstration than the actual execution of the threat. If it was necessary that every efficacious demonstration should be founded on the actual practicability of real action, which seems a matter of course at first sight, then it would accord with the same in all respects. But this is not the case: on the contrary, in the chapter on demonstrations we shall see that they are connected with conditions somewhat different, at all events in some respects, we therefore refer our readers to that chapter.

XXV. Retreat into the Interior of the Country

We have considered the voluntary retreat into the heart of the country as a particular indirect form of defence through which it is expected the enemy will be destroyed, not so much by the sword as by exhaustion from his own efforts. In this case, therefore, a great battle is either not supposed, or it is assumed to take place when the enemy’s forces are considerably reduced.

Every assailant in advancing diminishes his military strength by the advance; we shall consider this more in detail in the seventh book; here we must assume that result which we may the more readily do as it is clearly shown by military history in every campaign in which there has been a considerable advance.

This loss in the advance is increased if the enemy has not been beaten, but withdraws of his own accord with his forces intact, and offering a steady continuous resistance, sells every step of ground at a bloody price, so that the advance is a continuous combat for ground and not a mere pursuit.

On the other hand, the losses which a party on the defensive suffers on a retreat, are much greater if his retreat has been preceded by a defeat in battle than if his retreat is voluntary. For if he is able to offer the pursuer the daily resistance which we expect on a voluntary retreat, his losses would be at least the same in that way, over and above which those sustained in the battle have still to be added. But how contrary to the nature of the thing such a supposition as this would be! The best army in the world if obliged to retire far into the country after the loss of a battle, will suffer losses on the retreat, beyond measure out of proportion; and if the enemy is considerably superior, as we suppose him, in the case of which we are now speaking, if he pursues with great energy as has almost always been done in modern wars, then there is the highest probability that a regular flight takes place by which the army is usually completely ruined.

A regularly measured daily resistance, that is, one which each time only lasts as long as the balance of success in the combat can be kept wavering, and in which we secure ourselves from defeat by giving up the ground which has been contested at the right moment, will cost the assailant at least as many men as the defender in these combats, for the loss which the latter by retiring now and again must unavoidably suffer in prisoners, will be balanced by the losses of the other under fire, as the assailant must always fight against the advantages of the ground. It is true that the retreating side loses entirely all those men who are badly wounded, but the assailant likewise loses all his in the same case for the present, as they usually remain several months in the hospitals.

The result will be that the two armies will wear each other away in nearly equal proportions in these perpetual collisions.

It is quite different in the pursuit of a beaten army. Here the troops lost in battle, the general disorganisation, the broken courage, the anxiety about the retreat, make such a resistance on the part of the retreating army very difficult, in many cases impossible; and the pursuer who, in the former case, advances extremely cautiously, even hesitatingly, like a blind man, always groping about, presses forward in the latter case with the firm tread of the conqueror, with the overweening spirit which good fortune imparts, with the confidence of a demigod, and the more daringly he urges the pursuit so much the more he hastens on things in the direction which they have already taken, because here is the true field for the moral forces which intensify and multiply themselves without being restricted to the rigid numbers and measures of the physical world.

It is therefore very plain how different will be the relations of two armies according as it is by the first or the second of the above ways, that they arrive at that point which may be regarded as the end of the assailant’s course.

This is merely the result of the mutual destruction; to this must now be added the reductions which the advancing party suffers otherwise in addition, and respecting which, as already said, we refer to the seventh book; further, on the other hand, we have to take into account reinforcements which the retreating party receives in the great majority of cases, by forces subsequently joining him either in the form of help from abroad or through persistent efforts at home.

Lastly, there is, in the means of subsistence, such a disproportion between the retreating side and the advancing, that the first not uncommonly lives in superfluity when the other is reduced to want.

The army in retreat has the means of collecting provisions everywhere, and he marches towards them, whilst the pursuer must have everything brought after him, which, as long as he is in motion, even with the shortest lines of communication, is difficult, and on that account begets scarcity from the very first.

All that the country yields will be taken for the benefit of the retreating army first, and will be mostly consumed. Nothing remains but wasted villages and towns, fields from which the crops have been gathered, or which are trampled down, empty wells, and muddy brooks.

The pursuing army, therefore, from the very first day, has frequently to contend with the most pressing wants. On taking the enemy’s supplies he cannot reckon; it is only through accident, or some unpardonable blunder on the part of the enemy, that here and there some little falls into his hands.

Thus there can be no doubt that in countries of vast dimensions, and when there is no extraordinary disproportion between the belligerent powers, a relation may be produced in this way between the military forces, which holds out to the defensive an immeasurably greater chance of a final result in his favour than he would have had if there had been a great battle on the frontier. Not only does the probability of gaining a victory become greater through this alteration in the proportions of the contending armies, but the prospects of great results from the victory are increased as well, through the change of position. What a difference between a battle lost close to the frontier of our country and one in the middle of the enemy’s country! Indeed, the situation of the assailant is often such at the end of his first start, that even a battle gained may force him to retreat, because he has neither enough impulsive power left to complete and make use of a victory, nor is he in a condition to replace the forces he has lost.

There is, therefore, an immense difference between a decisive blow at the commencement and at the end of the attack.

To the great advantage of this mode of defence are opposed two drawbacks. The first is the loss which the country suffers through the presence of the enemy in his advance, the other is the moral impression.

To protect the country from loss can certainly never be looked upon as the object of the whole defence. That object is an advantageous peace. To obtain that as surely as possible is the endeavour, and for it no momentary sacrifice must he considered too great. At the same time, the above loss, although it may not be decisive, must still be laid in the balance, for it always affects our interests.

This loss does not affect our army directly; it only acts upon it in a more or less roundabout way, whilst the retreat itself directly reinforces our army. It is, therefore, difficult to draw a comparison between the advantage and disadvantage in this case; they are things of a different kind, the action of which is not directed towards any common point. We must, therefore, content ourselves with saying that the loss is greater when we have to sacrifice fruitful provinces well populated, and large commercial towns; but it arrives at a maximum when at the same time we lose war-means either ready for use or in course of preparation.

The second counterpoise is the moral impression. There are cases in which the commander must be above regarding such a thing, in which he must quietly follow out his plans, and run the risk of the objections which short-sighted despondency may offer; but nevertheless, this impression is no phantom which should be despised. It is not like a force which acts upon one point: but like a force which, with the speed of lightning, penetrates every fibre, and paralyses all the powers which should be in full activity, both in a nation and in its army. There are indeed cases in which the cause of the retreat into the interior of the country is quickly understood by both nation and army, and trust, as well as hope, are elevated by the step; but such cases are rare. More usually, the people and the army cannot distinguish whether it is a voluntary movement or a precipitate retreat, and still less whether the plan is one wisely adopted, with a view to ensure ulterior advantages, or the result of fear of the enemy’s sword. The people have a mingled feeling of sympathy and dissatisfaction at seeing the fate of the provinces sacrificed; the army easily loses confidence in its leaders, or even in itself, and the constant combats of the rear-guard during the retreat, tend always to give new strength to its fears. These are consequences of the retreat about which we must never deceive ourselves. And it certainly is—considered in itself—more natural, simpler, nobler, and more in accordance with the moral existence of a nation, to enter the lists at once, that the enemy may out cross the frontiers of its people without being opposed by its genius, and being called to a bloody account.

These are the advantages and disadvantages of this kind of defence; now a few words on its conditions and the circumstances which are in its favour.

A country of great extent, or at all events, a long line of retreat, is the first and fundamental condition; for an advance of a few marches will naturally not weaken the enemy seriously. Buonaparte’s centre, in the year 1812, at Witepsk, was 250,000 strong, at Smolensk, 182,000, at Borodino it had only diminished to 130,000, that is to say, had fallen to about an equality with the Russian centre. Borodino is ninety miles from the frontier; but it was not until they came near Moscow that the Russians reached that decided superiority in numbers, which of itself reversed the situation of the combatants so assuredly, that the French victory at Malo Jaroslewetz could not essentially alter it again.

No other European state has the dimensions of Russia, and in very few can a line of retreat 100 miles long be imagined. But neither will a power such as that of the French in 1812, easily appear under different circumstances, still less such a superiority in numbers as existed at the commencement of the campaign, when the French army had more than double the numbers of its adversary, besides its undoubted moral superiority. Therefore, what was here only effected at the end of 100 miles, may perhaps, in other cases, be attained at the end of 50 or 30 miles.

The circumstances which favour this mode of defence are—

1. A country only little cultivated.

2. A loyal and warlike people.

3. An inclement season.

All these things increase the difficulty of maintaining an army, render great convoys necessary, many detachments, harassing duties, cause the spread of sickness, and make operations against the flanks easier for the defender.

Lastly, we have yet to speak of the absolute mass alone of the armed force, as influencing the result.

It lies in the nature of the thing itself that, irrespective of the mutual relation of the forces opposed to each other, a small force is sooner exhausted than a larger, and, therefore, that its career cannot be so long, nor its theatre of war so wide. There is, therefore, to a certain extent, a constant relation between the absolute size of an army and the space which that army can occupy. It is out of the question to try to express this relation by any figures, and besides, it will always be modified by other circumstances; it is sufficient for our purpose to say that these things necessarily have this relation from their very nature. We may be able to march upon Moscow with 500,000 but not with 50,000, even if the relation of the invader’s army to that of the defender in point of numbers were much more favourable in the latter case.

Now if we assume that there is this relation of absolute power to space in two different cases, then it is certain that the effect of our retreat into the interior in weakening the enemy will increase with the masses.

1. Subsistence and lodging of the troops become more difficult—for, supposing the space which an army covers to increase in proportion to the size of the army, still the subsistence for the army will never be obtainable from this space alone, and everything which has to be brought after an army is subject to greater loss also; the whole space occupied is never used for covering for the troops, only a small part of it is required, and this does not increase in the same proportion as the masses.

2. The advance is in the same manner more tedious in proportion as the masses increase, consequently, the time is longer before the career of aggression is run out, and the sum total of the daily losses is greater.

Three thousand men driving two thousand before them in an ordinary country, will not allow them to march at the rate of 1, 2, or at most 3 miles a day, and from time to time to make a few days’ halt. To come up with them, to attack them, and force them to make a further retreat is the work of a few hours; but if we multiply these masses by 100, the case is altered. Operations for which a few hours sufficed in the first case, require now a whole day, perhaps two. The contending forces cannot remain together near one point; thereby, therefore, the diversity of movements and combinations increases, and, consequently, also the time required. But this places the assailant at a disadvantage, because his difficulty with subsistence being greater, he is obliged to extend his force more than the pursued, and, therefore, is always in danger of being overpowered by the latter at some particular point, as the Russians tried to do at Witepsk.

3. The greater the masses are, the more severe are the exertions demanded from each individual for the daily duties required strategically and tactically. A hundred thousand men who have to march to and from the point of assembly every day, halted at one time, and then set in movement again, now called to arms, then cooking or receiving their rations—a hundred thousand who must not go into their bivouac until the necessary reports are delivered in from all quarters—these men, as a rule, require for all these exertions connected with the actual march, twice as much time as 50,000 would require, but there are only twenty-four hours in the day for both. How much the time and fatigue of the march itself differs according to the size of the body of troops to be moved, has been shown in the ninth chapter of the preceding book. Now, the retreating army, it is true, partakes of these fatigues as well as the advancing, but they are much greater for the latter:—

1. because the mass of his troops is greater on account of the superiority which we supposed,

2. because the defender, by being always the party to yield ground, purchases by this sacrifice the right of the initiative, and, therefore, the right always to give the law to the other. He forms his plan beforehand, which, in most cases, he can carry out unaltered, but the aggressor, on the other hand, can only make his plans conformably to those of his adversary, which he must in the first instance find out.

We must, however, remind our readers that we are speaking of the pursuit of an enemy who has not suffered a defeat, who has not even lost a battle. It is necessary to mention this, in order that we may not be supposed to contradict what was said in the twelfth chapter of our fourth book.

But this privilege of giving the law to the enemy makes a difference in saving of time, expenditure of force, as well as in respect of other minor advantages which, in the long run, becomes very important.

3. because the retreating force on the one hand does all he can to make his own retreat easy, repairs roads, and bridges, chooses the most convenient places for encampment, etc., and, on the other hand again, does all he can to throw impediments in the way of the pursuer, as he destroys bridges, by the mere act of marching makes bad roads worse, deprives the enemy of good places for encampment by occupying them himself, etc.

Lastly, we must add still, as a specially favourable circumstance, the war made by the people. This does not require further examination here, as we shall allot a chapter to the subject itself.

Hitherto, we have been engaged upon the advantages which such a retreat ensures, the sacrifices which it requires, and the conditions which must exist; we shall now say something of the mode of executing it.

The first question which we have to propose to ourselves is with reference to the direction of the retreat.

It should be made into the interior of the country, therefore, if possible, towards a point where the enemy will be surrounded on all sides by our provinces; there he will be exposed to their influence, and we shall not be in danger of being separated from the principal mass of our territory, which might happen if we chose a line too near the frontier, as would have happened to the Russians in 1812 if they had retreated to the south instead of the east.

This is the condition which lies in the object of the measure itself. Which point in the country is the best, how far the choice of that point will accord with the design of covering the capital or any other important point directly, or drawing the enemy away from the direction of such important places depends on circumstances.

If the Russians had well considered their retreat in 1812 beforehand, and, therefore, made it completely in conformity with a regular plan, they might easily, from Smolensk, have taken the road to Kaluga, which they only took on leaving Moscow; it is very possible that under these circumstances Moscow would have been entirely saved.

That is to say, the French were about 130,000 strong at Borodino, and there is no ground for assuming that they would have been any stronger if this battle had been fought by the Russians half way to Kaluga instead; now, how many of these men could they have spared to detach to Moscow? Plainly, very few; but it is not with a few troops that an expedition can be sent a distance of fifty miles (the distance from Smolensk to Moscow) against such a place as Moscow.

Supposing Buonaparte when at Smolensk, where he was 160,000 strong, had thought he could venture to detach against Moscow before engaging in a great battle, and had used 40,000 men for that purpose, leaving 120,000 opposite the principal Russian army, in that case, these 120,000 men would not have been more than 90,000 in the battle, that is 40,000 less than the number which fought at Borodino; the Russians, therefore, would have had a superiority in numbers of 30,000 men. Taking the course of the battle of Borodino as a standard, we may very well assume that with such a superiority they would have been victorious. At all events, the relative situation of the parties would have been more favourable for the Russians than it was at Borodino. But the retreat of the Russians was not the result of a well-matured plan; they retreated as far as they did because each time that they were on the point of giving battle they did not consider themselves strong enough yet for a great action; all their supplies and reinforcements were on the road from Moscow to Smolensk, and it could not enter the head of anyone at Smolensk to leave that road. But, besides, a victory between Smolensk and Kaluga would never have excused, in the eyes of the Russians, the offence of having left Moscow uncovered, and exposed it to the possibility of being captured.

Buonaparte, in 1813, would have secured Paris with more certainty from an attack if he had taken up a position at some distance in a lateral direction, somewhere behind the canal of Burgundy, leaving only with the large force of National Guard in Paris a few thousand regular troops. The allies would never have had the courage to march a corps of 50,000 or 60,000 against Paris whilst Buonaparte was in the field at Auxerre with 100,000 men. If the case is supposed reversed, and the allies in Buonaparte’s place, then no one, indeed, would have advised them to leave the road open to their own capital with Buonaparte for their opponent. With such a preponderance he would not have hesitated a moment about marching on the capital. So different is the effect under the same circumstances but under different moral relations.

As we shall have hereafter to return to this subject when treating of the plan of a war, we shall only at present add that, when such a lateral position is taken, the capital or place which it is the object to protect, must, in every case, be capable of making some resistance that it may not be occupied and laid under contribution by every flying column or irregular band.

But we have still to consider another peculiarity in the direction of such a line of retreat, that is, a sudden change of direction. After the Russians had kept the same direction as far as Moscow they left that direction which would have taken them to Wladimir, and after first taking the road to Riazan for some distance, they then transferred their army to the Kaluga road. If they had been obliged to continue their retreat they could easily have done so in this new direction which would have led them to Kiew, therefore much nearer again to the enemy’s frontier. That the French, even if they had still preserved a large numerical superiority over the Russians, could not have maintained their line of communication by Moscow under such circumstances is clear in itself; they must have given up not only Moscow but, in all probability, Smolensk also, therefore have again abandoned the conquests obtained with so much toil, and contented themselves with a theatre of war on this side the Beresina.

Now, certainly, the Russian army would thus have got into the same difficulty to which it would have exposed itself by taking the direction of Kiew at first, namely, that of being separated from the mass of its own territory; but this disadvantage would now have become almost insignificant, for how different would have been the condition of the French army if it had marched straight upon Kiew without making the detour by Moscow.

It is evident that such a sudden change of direction of a line of retreat, which is very practicable in a spacious country, ensures remarkable advantages.

1. It makes it impossible for the enemy (the advancing force) to maintain his old line of communication: but the organisation of a new one is always a difficult matter, in addition to which the change is made gradually, therefore, probably, he has to try more than one new line.

2. If both parties in this manner approach the frontier again; the position of the aggressor no longer covers his conquests, and he must in all probability give them up.

Russia with its enormous dimensions, is a country in which two armies might in this manner regularly play at prisoners’ base (Zeck jagen).

But such a change of the line of retreat is also possible in smaller countries, when other circumstances are favourable, which can only be judged of in each individual case, according to its different relations.

When the direction in which the enemy is to be drawn into the country is once fixed upon, then it follows of itself that our principal army should take that direction, for otherwise the enemy would not advance in that direction, and if he even did we should not then be able to impose upon him all the conditions above supposed. The question then only remains whether we shall take this direction with our forces undivided, or whether considerable portions should spread out laterally and therefore give the retreat a divergent (eccentric) form.

To this we answer that this latter form in itself is to be rejected.

1. Because it divides our forces, whilst their concentration on one point is just one of the chief difficulties for the enemy.

2. Because the enemy gets the advantage of operating on interior lines, can remain more concentrated than we are, consequently can appear in so much the greater force at any one point. Now certainly this superiority is less to be dreaded when we are following a system of constantly giving way; but the very condition of this constantly yielding, is always to continue formidable to the enemy and not to allow him to beat us in detail, which might easily happen. A further object of such a retreat, is to bring our principal force by degrees to a superiority of numbers, and with this superiority to give a decisive blow, but that by a partition of forces would become an uncertainty.

3. Because as a general rule the concentric (convergent) action against the enemy is not adapted to the weaker forces.

4. Because many disadvantages of the weak points of the aggression disappear when the defender’s army is divided into separate parts.

The weakest features in a long advance on the part of the aggressor are for instance;—the length of the lines of communication, and the exposure of the strategic flanks. By the divergent form of retreat, the aggressor is compelled to cause a portion of his force to show a front to the flank, and this portion properly destined only to neutralise our force immediately in his front, now effects to a certain extent something else in addition, by covering a portion of the lines of communication.

For the mere strategic effect of the retreat, the divergent form is therefore not favourable; but if it is to prepare an action hereafter against the enemy’s line of retreat, then we must refer to what has been said about that in the last chapter.

There is only one object which can give occasion to a divergent retreat, that is when we can by that means protect provinces which otherwise the enemy would occupy.

What sections of territory the advancing foe will occupy right and left of his course, can with tolerable accuracy be discerned by the point of assembly of, and directions given to, his forces, by the situation of his own provinces, fortresses, etc., in respect to our own. To place troops in those districts of territory which he will in all probability leave unoccupied, would be dangerous waste of our forces. But now whether by any disposition of our forces we shall be able to hinder him from occupying those districts which in all probability he will desire to occupy, is more difficult to decide, and it is therefore a point, the solution of which depends much on tact of judgment.

When the Russians retreated in 1812, they left 30,000 men under Tormassow in Volhynia, to oppose the Austrian force which was expected to invade that province. The size of the province, the numerous obstacles of ground which the country presents, the near proportion between the forces likely to come into conflict justified the Russians in their expectations, that they would be able to keep the upper hand in that quarter, or at least to maintain themselves near to their frontier. By this, very important advantages might have resulted in the sequel, which we shall not stop here to discuss; besides this, it was almost impossible for these troops to have joined the main army in time if they had wished. For these reasons, the determination to leave these troops in Volhynia to carry on there a distinct war of their own, was right. Now on the other hand, if according to the proposed plan of campaign submitted by General Phul, only the army of Barclay (80,000 men), was to retire to Drissa, and Bragathion’s army (40,000 men) was to remain on the right flank of the French, with a view to subsequently falling on their rear, it is evident at once that this corps could not possibly maintain itself in South Lithuania so near to the rear of the main body of the French army, and would soon have been destroyed by their overwhelming masses.

That the defender’s interest in itself is to give up as few provinces as possible to the assailant is intelligible enough, but this is always a secondary consideration; that the attack is also made more difficult the smaller or rather narrower the theatre of war is to which we can confine the enemy, is likewise clear in itself; but all this is subordinate to the condition that in so doing we have the probability of a result in our favour, and that the main body of the force on the defensive will not be too much weakened; for upon that force we must chiefly depend for the final solution, because the difficulties and distress suffered by the main body of the enemy, first call forth his determination to retreat, and increase in the greatest degree the loss of physical and moral power therewith connected.

The retreat into the interior of the country should therefore as a rule be made directly before the enemy, and as slowly as possible, with an army which has not suffered defeat and is undivided; and by its incessant resistance it should force the enemy to a constant state of readiness for battle, and to a ruinous expenditure of forces in tactical and strategical measures of precaution.

When both sides have in this manner reached the end of the aggressor’s first start, the defender should then dispose his army in a position, if such can be found, forming an oblique angle with the route of his opponent, and operate against the enemy’s rear with all the means at his command.

The campaign of 1812 in Russia shows all these measures on a great scale, and their effects, as it were, in a magnifying glass. Although it was not a voluntary retreat, we may easily consider it from that point of view. If the Russians with the experience they now have of the results to be thus produced, had to undertake the defence of their country over again, exactly under the same circumstances, they would do voluntarily and systematically what in great part was done without a definite plan in 1812; but it would be a great mistake to suppose that there neither is nor can be any instance elsewhere of the same mode of action where the dimensions of the Russian empire are wanting.

Whenever a strategic attack, without coming to the issue of a battle, is wrecked merely on the difficulties encountered, and the aggressor is compelled to make a more or less disastrous retreat, there the chief conditions and principal effects of this mode of defence will be found to have taken place, whatever may be the modifying circumstances otherwise with which it is accompanied. Frederick the Great’s campaign of 1742 in Moravia, of 1744 in Bohemia, the French campaign of 1743 in Austria and Bohemia, the Duke of Brunswick’s campaign of 1792 in France, Massena’s winter campaign of 1810—11 in Portugal, are all cases in which this is exemplified, although in smaller proportions and relations; there are besides innumerable fragmentary operations of this kind, the results of which, although not wholly, are still partly to be ascribed to the principle which we here uphold; these we do not bring forward, because it would necessitate a development of circumstances which would lead us into too wide a field.

In Russia, and in the other cases cited, the crisis or turn of affairs took place without any successful battle, having given the decision at the culminating point; but even when such an effect is not to be expected, it is always a matter of immense importance in this mode of defence to bring about such a relation of forces as makes victory possible, and through that victory, as through a first blow, to cause a movement which usually goes on increasing in its disastrous effects according to the laws applicable to falling bodies.

XXVI. Arming the Nation

A people’s war in civilised Europe is a phenomenon of the nineteenth century. It has its advocates and its opponents: the latter either considering it in a political sense as a revolutionary means, a state of anarchy declared lawful, which is as dangerous as a foreign enemy to social order at home; or on military grounds, conceiving that the result is not commensurate with the expenditure of the nation’s strength. The first point does not concern us here, for we look upon a people’s war merely as a means of fighting, therefore, in its connection with the enemy; but with regard to the latter point, we must observe that a people’s war in general is to be regarded as a consequence of the outburst which the military element in our day has made through its old formal limits; as an expansion and strengthening of the whole fermentation-process which we call war. The requisition system, the immense increase in the size of armies by means of that system, and the general liability to military service, the utilizing militia, are all things which lie in the same direction, if we make the limited military system of former days our starting point; and the levée en masse, or arming of the people, now lies also in the same direction. If the first named of these new aids to war are the natural and necessary consequences of barriers thrown down; and if they have so enormously increased the power of those who first used them, that the enemy has been carried along in the current, and obliged to adopt them likewise, this will be the case also with people-wars. In the generality of cases, the people who make judicious use of this means, will gain a proportionate superiority over those who despise its use. If this be so, then the only question is whether this modern intensification of the military element is, upon the whole, salutary for the interests of humanity or otherwise,—a question which it would be about as easy to answer as the question of war itself—we leave both to philosophers. But the opinion may be advanced, that the resources swallowed up in people’s wars might be more profitably employed, if used in providing other military means; no very deep investigation, however, is necessary to be convinced that these resources are for the most part not disposable, and cannot be utilized in an arbitrary manner at pleasure. One essential part that is the moral element, is not called into existence until this kind of employment for it arises.

We therefore do not ask again: how much does the resistance which the whole nation in arms is capable of making, cost that nation? but we ask: what is the effect which such a resistance can produce? What are its conditions, and how is it to be used?

It follows from the very nature of the thing that defensive means thus widely dispersed, are not suited to great blows requiring concentrated action in time and space. Its operation, like the process of evaporation in physical nature, is according to the surface. The greater that surface and the greater the contact with the enemy’s army, consequently the more that army spreads itself out, so much the greater will be the effects of arming the nation. Like a slow gradual heat, it destroys the foundations of the enemy’s army. As it requires time to produce its effects, therefore whilst the hostile elements are working on each other, there is a state of tension which either gradually wears out if the people’s war is extinguished at some points, and burns slowly away at others, or leads to a crisis, if the flames of this general conflagration envelop the enemy’s army, and compel it to evacuate the country to save itself from utter destruction. In order that this result should be produced by a national war alone, we must suppose either a surface-extent of the dominions invaded, exceeding that of any country in Europe, except Russia, or suppose a disproportion between the strength of the invading army and the extent of the country, such as never occurs in reality. Therefore, to avoid following a phantom, we must imagine a people-war always in combination, with a war carried on by a regular army, and both carried on according to a plan embracing the operations of the whole.

The conditions under which alone the people’s war can become effective are the following—

1. That the war is carried on in the heart of the country.

2. That it cannot be decided by a single catastrophe.

3. That the theatre of war embraces a considerable extent of country.

4. That the national character is favourable to the measure.

5. That the country is of a broken and difficult nature, either from being mountainous, or by reason of woods and marshes, or from the peculiar mode of cultivation in use.

Whether the population is dense or otherwise, is of little consequence, as there is less likelihood of a want of men than of anything else. Whether the inhabitants are rich or poor is also a point by no means decisive, at least it should not be; but it must be admitted that a poor population accustomed to hard work and privations usually shows itself more vigorous and better suited for war.

One peculiarity of country which greatly favors the action of war carried on by the people, is the scattered sites of the dwellings of the country people, such as is to be found in many parts of Germany. The country is thus more intersected an dcovered; the roads are worse, although more numerous; the lodgement of troops is attended with endless difficulties, but especially that peculiarity repeats itself on a small scale, which a people-war possesses on a great scale, namely that the principle of resistance exists everywhere, but is nowhere tangible. If the inhabitants are collected in villages, the most troublesome have troops quartered on them, or they are plundered as a punishment, and their houses burnt, etc, a system which could not be very easily carried out with a peasant community of Westphalia.

National levies and armed peasantry cannot and should not be employed against the main body of the enemy’s army, or even against any considerable corps of the same, they must not attempt to crack the nut, they must only gnaw on the surface and the borders. They should rise in the provinces situated at one of the sides of the theatre of war, and in which the assailant does not appear in force, in order to withdraw these provinces entirely from his influence. Where no enemy is to be found, there is no want of courage to oppose him, and at the example thus given, the mass of the neighboring population gradually takes fire. Thus the fire spreads as it does in heather, and reaching at last that part of the surface of the soil on which the aggressor is based, it seizes his lines of communication and preys upon the vital thread by which his existence is supported. For although we entertain no exaggerated ideas of the omnipotence of a people’s war, such as that it is an inexhaustible, unconquerable element, over which the mere force of an army has as little control as the human will has over the wind or the rain; in short, although our opinion is not founded on flowery ephemeral literature, still we must admit that armed peasants are not to be driven before us in the same way as a body of soldiers who keep together like a herd of cattle, and usually follow their noses. Armed peasants, on the contrary, when broken, disperse in all directions, for which no formal plan is required; through this circumstance, the march of every small body of troops in a mountainous, thickly wooded, or even broken country, becomes a service of a very dangerous character, for at any moment a combat may arise on the march; if in point of fact no armed bodies have even been seen for some time, yet the same peasants already driven off by the head of a column, may at any hour make their appearance in its rear. If it is an object to destroy roads or to block up a defile; the means which outposts or detachments from an army can apply to that purpose, bear about the same relation to those furnished by a body of insurgent peasants, as the action of an automaton does to that of a human being. The enemy has no other means to oppose to the action of national levies except that of detaching numerous parties to furnish escorts for convoys to occupy military stations, defiles, bridges, etc. In proportion as the first efforts of the national levies are small, so the detachments sent out will be weak in numbers, from the repugnance to a great dispersion of forces; it is on these weak bodies that the fire of the national war usually first properly kindles itself, they are overpowered by numbers at some points, courage rises, the love of fighting gains strength, and the intensity of this struggle increases until the crisis approaches which is to decide the issue.

According to our idea of a people’s war, it should, like a kind of nebulous vapoury essence, never condense into a solid body; otherwise the enemy sends an adequate force against this core, crushes it, and makes a great many prisoners; their courage sinks; every one thinks the main question is decided, any further effort useless, and the arms fall from the hands of the people. Still, however, on the other hand, it is necessary that this mist should collect at some points into denser masses, and form threatening clouds from which now and again a formidable flash of lightning may burst forth. These points are chiefly on the flanks of the enemy’s theatre of war, as already observed. There the armament of the people should be organised into greater and more systematic bodies, supported by a small force of regular troops, so as to give it the appearance of a regular force and fit it to venture upon enterprises on a larger scale. From these points, the irregular character in the organisation of these bodies should diminish in proportion as they are to be employed more in the direction of the rear of the enemy, where he is exposed to their hardest blows. These better organised masses, are for the purpose of falling upon the larger garrisons which the enemy leaves behind him. Besides, they serve to create a feeling of uneasiness and dread, and increase the moral impression of the whole, without them the total action would be wanting in force, and the situation of the enemy upon the whole would not be made sufficiently uncomfortable.

The easiest way for a general to produce this more effective form of a national armament, is to support the movement by small detachments sent from the army. Without the support of a few regular troops as an encouragement, the inhabitants generally want an impulse, and the confidence to take up arms. The stronger these detachments are, the greater will be their power of attraction, the greater will be the avalanche which is to fall down. But this has its limits; partly, first, because it would be detrimental to the army to cut it up into detachments, for this secondary object to dissolve it, as it were, into a body of irregulars, and form with it in all directions a weak defensive line, by which we may be sure both the regular army and national levies alike would become completely ruined; partly, secondly, because experience seems to tell us that when there are too many regular troops in a district, the people-war loses in vigour and efficacy; the causes of this are in the first place, that too many of the enemy’s troops are thus drawn into the district, and, in the second place, that the inhabitants then rely on their own regular troops, and, thirdly, because the presence of such large bodies of troops makes too great demands on the powers of the people in other ways, that is, in providing quarters, transport, contributions, etc., etc.

Another means of preventing any serious reaction on the part of the enemy against this popular movement constitutes, at the same time, a leading principle in the method of using such levies; this is, that as a rule, with this great strategic means of defence, a tactical defence should seldom or ever take place. The character of a combat with national levies is the same as that of all combats of masses of troops of an inferior quality, great impetuosity and fiery ardour at the commencement, but little coolness or tenacity if the combat is prolonged. Further, the defeat and dispersion of a body of national levies is of no material consequence, as they lay their account with that, but a body of this description must not be broken up by losses in killed, wounded, and prisoners; a defeat of that kind would soon cool their ardour. But both these peculiarities are entirely opposed to the nature of a tactical defensive. In the defensive combat a persistent slow systematic action is required, and great risks must be run; a mere attempt, from which we can desist as soon as we please, can never lead to results in the defensive. If, therefore, the national levies are entrusted with the defence of any particular portion of territory, care must be taken that the measure does not lead to a regular great defensive combat; for if the circumstances were ever so favourable to them, they would be sure to be defeated. They may, and should, therefore, defend the approaches to mountains, dykes, over marshes, river-passages, as long as possible; but when once they are broken, they should rather disperse, and continue their defence by sudden attacks, than concentrate and allow themselves to be shut up in some narrow last refuge in a regular defensive position.—However brave a nation may be, however warlike its habits, however intense its hatred of the enemy, however favourable the nature of the country, it is an undeniable fact that a people’s war cannot be kept up in an atmosphere too full of danger. If, therefore, its combustible material is to be fanned by any means into a considerable flame it must be at remote points where there is more air, and where it cannot be extinguished by one great blow.

After these reflections, which are more of the nature of subjective impressions than an objective analysis, because the subject is one as yet of rare occurrence generally, and has been but imperfectly treated of by those who have had actual experience for any length of time, we have only to add that the strategic plan of defence can include in itself the cooperation of a general arming of the people in two different ways, that is, either as a last resource after a lost battle, or as a natural assistance before a decisive battle has been fought. The latter case supposes a retreat into the interior of the country, and that indirect kind of reaction of which we have treated in the eighth and twenty-fourth chapters of this book. We have, therefore, here only to say a few words on the mission of the national levies after a battle has been lost.

No State should believe its fate, that is, its entire existence, to be dependent upon one battle, let it be even the most decisive. If it is beaten, the calling forth fresh power, and the natural weakening which every offensive undergoes with time, may bring about a turn of fortune, or assistance may come from abroad. No such urgent haste to die is needed yet; and as by instinct the drowning man catches at a straw, so in the natural course of the moral world a people should try the last means of deliverance when it sees itself hurried along to the brink of an abyss.

However small and weak a State may be in comparison to its enemy, if it foregoes a last supreme effort, we must say there is no longer any soul left in it. This does not exclude the possibility of saving itself from complete destruction by the purchase of peace at a sacrifice; but neither does such an aim on its part do away with the utility of fresh measures for defence; they will neither make peace more difficult nor more onerous, but easier and better. They are still more necessary if there is an expectation of assistance from those who are interested in maintaining our political existence. Any government, therefore, which, after the loss of a great battle, only thinks how it may speedily place the nation in the lap of peace, and unmanned by the feeling of great hopes disappointed, no longer feels in itself the courage or the desire to stimulate to the utmost every element of force, completely stultifies itself in such case through weakness, and shows itself unworthy of victory, and, perhaps, just on that account, was incapable of gaining one.

However decisive, therefore, the overthrow may be which is experienced by a State, still by a retreat of the army into the interior, the efficacy of its fortresses and an arming of the people may be brought into use. In connection with this it is advantageous if the flank of the principal theatre of war is fenced in by mountains, or otherwise very difficult tracts of country, which stand forth as bastions, the strategic enfilade of which is to check the enemy’s progress.

If the victorious enemy is engaged in siege works, if he has left strong garrisons behind him everywhere to secure his communications, or detached corps to make himself elbow-room, and to keep the adjacent provinces in subjection, if he is already weakened by his various losses in active means and material of war, then the moment is arrived when the defensive army should again enter the lists, and by a well-directed blow make the assailant stagger in his disadvantageous position.

XXVII. Defence of a Theatre of War

Having treated of the most important defensive means, we might perhaps be contented to leave the manner in which these means attach themselves to the plan of defence as a whole to be discussed in the last Book, which will be devoted to the Plan of a War; for from this every secondary scheme, either of attack or defence, emanates and is determined in its leading features; and moreover in many cases the plan of the war itself is nothing more than the plan of the attack or defence of the principal theatre of war. But we have not been able to commence with war as a whole, although in war more than in any other phase of human activity, the parts are shaped by the whole, imbued with and essentially altered by its character; instead of that, we have been obliged to make ourselves thoroughly acquainted, in the first instance, with each single subject as a separate part. Without this progress from the simple to the complex, a number of undefined ideas would have overpowered us, and the manifold phases of reciprocal action in particular would have constantly confused our conceptions. We shall therefore still continue to advance towards the whole by one step at a time; that is, we shall consider the defence of a theatre in itself, and look for the thread by which the subjects already treated of connect themselves with it.

The defensive, according to our conception, is nothing but the stronger form of combat. The preservation of our own forces and the destruction of those of the enemy—in a word, the victory—is the aim of this contest, but at the same time not its ultimate object.

That object is the preservation of our own political state and the subjugation of that of the enemy; or again, in one word, the desired peace, because it is only by it that this conflict adjusts itself, and ends in a common result.

But what is the enemy’s state in connection with war? Above all things its military force is important, then its territory; but certainly there are also still many other things which, through particular circumstances, may obtain a predominant importance; to these belong, before all, foreign and domestic political relations, which sometimes decide more than all the rest. But although the military force and the territory of the enemy alone are still not the state itself, nor are they the only connections which the state may have with the war, still these two things are always preponderating, mostly immeasurably surpassing all other connections in importance. Military force is to protect the territory of the state, or to conquer that of an enemy; the territory on the other hand, constantly nourishes and renovates the military force. The two, therefore, depend on each other, mutually support each other, are equal in importance one to the other. But still there is a difference in their mutual relations. If the military force is destroyed, that is completely defeated, rendered incapable of further resistance, then the loss of the territory follows of itself; but on the other hand, the destruction of the military force by no means follows from the conquest of the country, because that force may of its own accord evacuate the territory, in order afterwards to reconquer it the more easily. Indeed, not only does the complete destruction of its army decide the fate of a country, but even every considerable weakening of its military force leads regularly to a loss of territory; on the other hand, every considerable loss of territory does not cause a proportionate diminution of military power; in the long run it will do so, but not always within the space of time in which a war is brought to a close.

From this it follows that the preservation of our own military power, and the diminution or destruction of that of the enemy, take precedence in importance over the occupation of territory, and, therefore, is the first object which a general should strive for. The possession of territory only presses for consideration as an object if that means (diminution or destruction of the enemy’s military force) has not effected it.

If the whole of the enemy’s military power was united in one army, and if the whole war consisted of one battle, then the possession of the country would depend on the issue of that battle; destruction of the enemy’s military forces, conquest of his country and security of our own, would follow from that result, and, in a certain measure, be identical with it. Now the question is, what can induce the defensive to deviate from this simplest form of the act of warfare, and distribute his power in space? The answer is, the insufficiency of the victory which he might gain with all his forces united. Every victory has its sphere of influence. If this extends over the whole of the enemy’s state, consequently over the whole of his military force and his territory, that is, if all the parts are carried along in the same movement, which we have impressed upon the core of his power, then such a victory is all that we require, and a division of our forces would not be justified by sufficient grounds. But if there are portions of the enemy’s military force, and of country belonging to either party, over which our victory would have no effect, then we must give particular attention to those parts; and as we cannot unite territory like a military force in one point, therefore we must divide our forces for the purpose of attacking or defending those portions.

It is only in small, compactly shaped states that it is possible to have such a unity of military force, and that probably all depends upon a victory over that force. Such a unity is practically impossible when larger tracts of country, having for a great extent boundaries conterminious with our own, are concerned, or in the case of an alliance of several surrounding states against us. In such cases, divisions of force must necessarily take place, giving occasion to different theatres of war.

The effect of a victory will naturally depend on its greatness, and that on the mass of the conquered troops. Therefore the blow which, if successful, will produce the greatest effect, must be made against that part of the country where the greatest number of the enemy’s forces are collected together; and the greater the mass of our own forces which we use for this blow, so much the surer shall we be of this success. This natural sequence of ideas leads us to an illustration by which we shall see this truth more clearly; it is the nature and effect of the centre of gravity in mechanics.

As the centre of gravity is always situated where the greatest mass of matter is collected, and as a shock against the centre of gravity of a body always produces the greatest effect, and further, as the most effective blow is struck with the centre of gravity of the power used, so it is also in war. The armed forces of every belligerent, whether of a single state or of an alliance of states, have a certain unity, and in that way, connection; but where connection is there come in analogies of the centre of gravity. There are, therefore, in these armed forces certain centres of gravity, the movement and direction of which decide upon other points, and these centres of gravity are situated where the greatest bodies of troops are assembled. But just as, in the world of inert matter, the action against the centre of gravity has its measure and limits in the connection of the parts, so it is in war, and here as well as there the force exerted may easily be greater than the resistance requires, and then there is a blow in the air, a waste of force.

What a difference there is between the solidity of an army under one standard, led into battle under the personal command of one general, and that of an allied army extended over 50 or 100 miles, or it may be even based upon quite different sides (of the theatre of war). There we see coherence in the strongest degree, unity most complete; here unity in a very remote degree often only existing in the political view held in common, and in that also in a miserable and insufficient degree, the cohesion of parts mostly very weak, often quite an illusion.

Therefore, if on the one hand, the violence with which we wish to strike the blow prescribes the greatest concentration of force, so in like manner, on the other hand, we have to fear every undue excess as a real evil, because it entails a waste of power, and that in turn a deficiency of power at other points.

To distinguish these “centra gravitatis” in the enemy’s military power, to discern their spheres of action is, therefore, a supreme act of strategic judgment. We must constantly ask ourselves, what effect the advance or retreat of part of the forces on either side will produce on the rest.

We do not by this lay claim in any way to the discovery of a new method, we have only sought to explain the foundation of the method of all generals, in every age, in a manner which may place its connection with the nature of things in a clearer light.

How this conception of the centre of gravity of the enemy’s force affects the whole plan of the war, we shall consider in the last book, for that is the proper place for the subject, and we have only borrowed it from there to avoid leaving any break in the sequence of ideas. By the introduction of this view we have seen the motives which occasion a partition of forces in general. These consist fundamentally of two interests which are in opposition to each other; the one, the possession of territory strives to divide the forces; the other, the effort of force against the centre of gravity of the enemy’s military power, combines them again up to a certain point.

Thus it is that theatres of war or particular army regions originate. These are those boundaries of the area of the country and of the forces thereon distributed, within which every decision given by the principal force of such a region extends itself directly over the whole, and carries on the whole with it in its own direction. We say directly, because a decision on one theatre of war must naturally have also an influence more or less over those adjoining it.

Although it lies quite in the nature of the thing, we must again remind our readers expressly that here as well as everywhere else our definitions are only directed at the centres of certain speculative regions, the limits of which we neither desire to, nor can we, define by sharp lines.

We think, therefore, a theatre of war, whether large or small, with its military force, whatever may be the size of that, represents a unity which maybe reduced to one centre of gravity. At this centre of gravity the decision must take place, and to be conqueror here means to defend the theatre of war in the widest sense.

XXVIII. Defence of a Theatre of War—(continued)

Defence, however, consists of two different elements, these are the decision and the state of expectation. The combination of these two elements forms the subject of this chapter.

First we must observe that the state of expectation is not, in point of fact, the complete defence; it is only that province of the same in which it proceeds to its aim. As long as a military force has not abandoned the portion of territory placed under its guardianship, the tension of forces on both sides created by the attack continues, and this lasts until there is a decision. The decision itself can only be regarded as having actually taken place when either the assailant or defender has left the theatre of war.

As long as an armed force maintains itself within its theatre, the defence of the same continues, and in this sense the defence of the theatre of war is identical with the defence in the same. Whether the enemy in the meantime has obtained possession of much or little of that section of country is not essential, for it is only lent to him until the decision.

But this kind of idea by which we wish to settle the proper relation of the state of expectation to the whole is only correct when a decision is really to take place, and is regarded by both parties as inevitable. For it is only by that decision that the centres of gravity of the respective forces, and the theatre of war determined through them are effectually hit. Whenever the idea of a decisive solution disappears, then the centres of gravity are neutralised, indeed, in a certain sense, the whole of the armed forces become so also, and now the possession of territory, which forms the second principal branch of the whole theatre of war, comes forward as the direct object. In other words, the less a decisive blow is sought for by both sides in a war, and the more it is merely a mutual observation of one another, so much the more important becomes the possession of territory, so much the more the defensive seeks to cover all directly, and the assailant seeks to extend his forces in his advance.

Now we cannot conceal from ourselves the fact that the majority of wars and campaigns approach much more to a state of observation than to a struggle for life or death, that is, a contest in which one at least of the combatants uses every effort to bring about a complete decision. This last character is only to be found in the wars of the nineteenth century to such a degree that a theory founded on this point of view can be made use of in relation to them. But as all future wars will hardly have this character, and it is rather to be expected that they will again show a tendency to the observation character, therefore any theory to be practically useful must pay attention to that. Hence we shall commence with the case in which the desire of a decision permeates and guides the whole, therefore with real, or if we may use the expression, absolute war; then in another chapter we shall examine those modifications which arise through the approach, in a greater or less degree, to the state of a war of observation.

In the first case (whether the decision is sought by the aggressor or the defender) the defence of the theatre of war must consist in the defender establishing himself there in such a manner, that in a decision he will have an advantage on his side at any moment. This decision may be either a battle, or a series of great combats, but it may also consist in the resultant of mere relations, which arise from the situation of the opposing forces, that is, possible combats.

If the battle were not also the most powerful, the most usual and most effectual means of a decision in war, as we think we have already shown on several occasions, still the mere fact of its being in a general way one of the means of reaching this solution, would be sufficient to enjoin the greatest concentration of our forces which circumstances will in any way permit. A great battle upon the theatre of war is the blow of the centre of force against the centre of force; the more forces can be collected in the one or the other, the surer and greater will be the effect. Therefore every separation of forces which is not called for by an object (which either cannot itself be attained by the successful issue of a battle, or which itself is necessary to the successful issue of the battle) is blameable.

But the greatest concentration of forces is not the only fundamental condition; it is also requisite that they should have such a position and place that the battle may be fought under favourable circumstances.

The different steps in the defence which we have become acquainted with in the chapter on the methods of defence, are completely homogeneous with these fundamental conditions; there will therefore be no difficulty in connecting them with the same, according to the special requirements of each case. But there is one point which seems at first sight to involve a contradiction in itself, and which, as one of the most important in the defence, requires explanation so much the more. It is the hitting upon the exact centre of gravity of the enemy’s force.

If the defender ascertains in time the roads by which the enemy will advance, and upon which in particular the great mass of his force will be found for a certainty, he may march against him on that road. This will be the most usual case, for although the defence precedes the attack in measures of a general nature, in the establishment of strong places, great arsenals, and depôts, and in the peace establishment of his army, and thus gives a line of direction to the assailant in his preparations, still, when the campaign really opens, the defender, in relation to the aggressor, has the peculiar advantage in general of playing the last hand.

To attack a foreign country with a large army, very considerable preparations are required. Provisions, stores, and articles of equipment of all kinds must be collected, which is a work of time. While these preparations are going on, the defender has time to prepare accordingly, in regard to which we must not forget that the defensive requires less time, generally speaking, because in every state things are prepared rather for the defensive than the offensive.

But although this may hold good in the majority of cases, there is always a possibility that, in particular cases, the defensive may remain in uncertainty as to the principal line by which the enemy intends to advance; and this case is more likely to occur when the defence is dependent on measures which of themselves take a good deal of time, as for example, the preparation of a strong position. Further, supposing the defender places himself on the line by which the aggressor is advancing, then, unless the defender is prepared to take the initiative by attacking the aggressor, the latter may avoid the position which the defender has taken up, by only altering a little his line of advance, for in the cultivated parts of Europe we can never be so situated that there are not roads to the right or left by which any position may be avoided. Plainly, in such a case the defender could not wait for his enemy in a position, or at least could not wait there in the expectation of giving battle.

But before entering on the means available to the defensive in this case, we must inquire more particularly into the nature of such a case, and the probability of its occurrence.

Naturally there are in every State, and also in every theatre of war (of which alone we are at present speaking), objects and points upon which an attack is likely to be more efficacious than anywhere else. Upon this we think it will be better to speak when we come to the attack. Here we shall confine ourselves to observing that, if the most advantageous object and point of attack is the motive for the assailant in the direction of his blow, this motive reacts on the defensive, and must be his guide in cases in which he knows nothing of the intentions of his adversary. If the assailant does not take this direction which is favourable to him, he foregoes part of his natural advantages. It is evident that, if the defender has taken up a position in that direction, the evading his position, or passing round, is not to be done for nothing; it costs a sacrifice. From this it follows that there is not on the side of the defender such a risk of missing the direction of his enemy; neither on the other hand, is it so easy for the assailant to pass round his adversary as appears at first sight, because there exists beforehand a very distinct, and in most cases preponderating, motive in favour of one or the other direction, and that consequently the defender, although his preparations are fixed to one spot, will not fail in most cases to come in contact with the mass of the enemy’s forces. In other words, if the defender has put himself in the right position, he may be almost sure that the assailant will come to meet him.

But by this we shall not and cannot deny the possibility of the defender sometimes not meeting with the assailant after all these arrangements, and therefore the question arises, what he should then do, and how much of the real advantages of his position still remain available to him.

If we ask ourselves what means still remain generally to the defender when the assailant passes by his position, they are the following:—

1. To divide his forces instantly, so as to be certain to find the assailant with one portion, and then to support that portion with the other.

2. To take up a position with his force united, and in case the assailant passes by him, to push on rapidly in front of him by a lateral movement. In most cases there will not be time to make such a movement directly to a flank, it will therefore be necessary to take up the new position somewhat further back.

3. With his whole force to attack the enemy in flank.

4. To operate against his communications.

5. By a counter attack on his theatre of war, to do exactly what the enemy has done in passing by us.

We introduce this last measure, because it is possible to imagine a case in which it may be efficacious; but as it is in contradiction to the object of the defence, that is, the grounds on which that form has been chosen, therefore it can only be regarded as an abnormity, which can only take place because the enemy has made some great mistake, or because there are other special features in a particular case.

Operating against the enemy’s communications implies that our own are superior, which is also one of the fundamental requisites of a good defensive position. But although on that ground this action may promise the defender a certain amount of advantage, still, in the defence of a theatre of war, it is seldom an operation suited to lead to a decision, which we have supposed to be the object of the campaign.

The dimensions of a single theatre of war are seldom so large that the line of communications is exposed to much danger by their length, and even if they were in danger, still the time which the assailant requires for the execution of his blow is usually too short for his progress to be arrested by the slow effects of the action against his communications.

Therefore this means (that is the action against the communications) will prove quite inefficacious in most cases against an enemy determined upon a decision, and also in case the defender seeks such a solution.

The object of the three other means which remain for the defender, is a direct decision—a meeting of centre of force with centre of force; they correspond better, therefore, with the thing required. But we shall at once say that we decidedly prefer the third to the other two, and without quite rejecting the latter, we hold the former to be in the majority of cases the true means of defence.

In a position where our forces are divided, there is always a danger of getting involved in a war of posts, from which, if our adversary is resolute, can follow, under the best of circumstances, only a relative defence on a large scale, never a decision such as we desire; and even if by superior tact we should be able to avoid this mistake, still, by the preliminary resistance being with divided forces, the first shock is sensibly weakened, and we can never be sure that the advanced corps first engaged will not suffer disproportionate losses. To this is to be added that the resistance of this corps which usually ends in its falling back on the main body, appears to the troops in the light of a lost combat, or miscarriage of plans, and the moral force suffers accordingly.

The second means, that of placing our whole force in front of the enemy, in whichever direction he may bend his march, involves a risk of our arriving too late, and thus between two measures, falling short of both. Besides this, a defensive battle requires coolness and consideration, a knowledge, indeed intimate knowledge of the country, which cannot be expected in a hasty oblique movement to a flank. Lastly, positions suitable for a good defensive battle-field are too rarely to be met with to reckon upon them at every point of every road.

On the other hand, the third means, namely to attack the enemy in flank, therefore to give battle with a change of front, is attended with great advantages.

Firstly, there is always in this case, as we know, an exposure of the lines of communication, here the lines of retreat, and in this respect the defender has one advantage in his general relations as defender, and next and chiefly, the advantage which we have claimed for the strategic properties of his position at present.

Secondly,—and this is the principal thing,—every assailant who attempts to pass by his opponent is placed between two opposite tendencies. His first desire is to advance to attain the object of his attack; but the possibility of being attacked in flank at any moment, creates a necessity for being prepared, at any moment, to deliver a blow in that direction, and that too a blow with the mass of his forces. These two tendencies are contradictory, and beget such a complication in the internal relations (of his army), such a difficulty in the choice of measures, if they are to suit every event, that there can hardly be a more disagreeable position strategically. If the assailant knew with certainty the moment when he would be attacked, he might prepare to receive the enemy with skill and ability; but in his uncertainty on this point, and pressed by the necessity of advancing, it is almost certain that when the moment for battle arrives, it finds him in the midst of hurried and half-finished preparations, and therefore by no means in an advantageous relation to his enemy.

If then there are favourable moments for the defender to deliver an offensive battle, it is surely at such a moment as this, above all others, that we may look for success. If we consider, further, that the knowledge of the country and choice of ground are on the side of the defender, that he can prepare his movements, and can time them, no one can doubt that he possesses in such a situation a decided superiority, strategically, over his adversary.

We think, therefore, that a defender occupying a well chosen position, with his forces united, may quietly wait for the enemy passing by his army; should the enemy not attack him in his position, and that an operation against the enemy’s communications does not suit the circumstances, there still remains for him an excellent means of bringing about a decision by resorting to a flank attack.

If cases of this kind are hardly to be found in military history, the reason is, partly, that the defender has seldom had the courage to remain firm in such a position, but has either divided his forces, or rashly thrown himself in front of his enemy by a cross or diagonal march, or that no assailant dares to venture past the defender under such circumstances, and in that way his movement usually comes to a stand still.

The defender is in this case compelled to resort to an offensive battle: the further advantages of the state of expectation of a strong position, of good entrenchments, etc., etc., he must give up; in most cases the situation in which he finds the advancing enemy will not quite make up for these advantages, for it is just to evade their influence that the assailant has placed himself in his present situation; still it always offers him a certain compensation, and theory is therefore not just obliged to see a quantity disappear at once from the calculation, to see the pro and contra mutually cancel each other, as so often happens when critical writers of history introduce a little bit of theory.

It must not, in fact, be supposed that we are now dealing with logical subtilties; the subject is rather one which the more it is practically considered, the more it appears as an idea embracing the whole essence of defensive war, everywhere dominating and regulating it.

It is only by the determination on the part of the defender to assail his opponent with all his force, the moment he passes by him, that he avoids two pitfalls, close to which he is led by the defensive form; that is a division of his force, and a hasty flank march to intercept the assailant in front. In both he accepts the law of the assailant; in both he seeks to aid himself through measures of a very critical nature, and with a most dangerous degree of haste; and wherever a resolute adversary, thirsting for victory and a decision, has encountered such a system of defence, he has knocked it on the head. But when the defender has assembled his forces at the right point to fight a general action, if he is determined with this force, come what will, to attack his enemy in flank, he has done right, and is in the right course, and he is supported by all the advantages which the defence can give in his situation; his actions will then bear the stamp of good preparation, coolness, security, unity and simplicity.

We cannot here avoid mentioning a remarkable event in history, which has a close analogy with the ideas now developed; we do so to anticipate its being used in a wrong application.

When the Prussian army was, in October, 1806, waiting in Thuringia for the French under Buonaparte, the former was posted between the two great roads on which the latter might be expected to advance, that is, the road to Berlin by Erfurth, and that by Hof and Leipsic. The first intention of breaking into Franconia straight through the Thuringian Forest, and afterwards, when that plan was abandoned, the uncertainty as to which of the roads the French would choose for their advance, caused this intermediate position. As such, it must therefore have led to the adoption of the measure we have been discussing, a hasty interception of the enemy in front by a lateral movement.

This was in fact the idea in case the enemy marched by Erfurth, for the roads in that direction were good; on the other hand, the idea of a movement of this description on the road by Hof could not be entertained, partly because the army was two or three marches away from that road, partly because the deep valley of the Saale interposed; neither did this plan ever enter into the views of the Duke of Brunswick, so that there was no kind of preparation made for carrying it into effect, but it was always contemplated by Prince Hohenlohe, that is, by Colonel Massenbach, who exerted all his influence to draw the Duke into this plan. Still less could the idea be entertained of leaving the position which had been taken on the left bank of the Saale to try an offensive battle against Buonaparte on his advance, that is, to such an attack in flank as we have been considering; for if the Saale was an obstacle to intercepting the enemy in the last moment (à fortiori) it would be a still greater obstacle to assuming the offensive at a moment when the enemy would be in possession of the opposite side of the river, at least partially. The Duke, therefore, determined to wait behind the Saale to see what would happen, that is to say, if we can call anything a determination which emanated from this many-headed Headquarters’ Staff, and in this time of confusion and utter indecision.

Whatever may have been the true condition of affairs during this state of expectation, the consequent situation of the army was this:—

1. That the enemy might be attacked if he crossed the Saale to attack the Prussian army.

2. That if he did not march against that army, operations might be commenced against his communications.

3. If it should be found practicable and advisable, he might be intercepted near Leipsic by a rapid flank march.

In the first case, the Prussian army possessed a great strategic and tactical advantage in the deep valley of the Saale. In the second, the strategic advantage was just as great, for the enemy had only a very narrow base between our position and the neutral territory of Bohemia, whilst ours was extremely broad; even in the third case, our army, covered by the Saale, was still by no means in a disadvantageous situation. All these three measures, in spite of the confusion and want of any clear perception at head-quarters, were really discussed; but certainly we cannot wonder that, although a right idea may have been entertained, it should have entirely failed in the execution by the complete want of resolution and the confusion generally prevailing.

In the two first cases, the position on the left bank of the Saale is to be regarded as a real flank position, and it had undoubtedly as such very great qualities; but in truth, against a very superior enemy, against a Buonaparte, a flank position with an army that is not very sure about what it is doing, is a very bold measure.

After long hesitation, the Duke on the 13th adopted the last of the plans proposed, but it was too late, Buonaparte had already commenced to pass the Saale, and the battles of Jena and Auerstadt were inevitable. The Duke, through his indecision, had set himself between two stools; he quitted his first position too late to push his army in before the enemy, and too soon for a battle suited to the object. Nevertheless, the natural strength of this position proved itself so far that the Duke was able to destroy the right wing of the enemy’s army at Auerstadt, whilst Prince Hohenlohe, by a bloody retreat, was still able to back out of the scrape; but at Auerstadt they did not venture to realise the victory, which was quite certain; and at Jena they thought they might reckon upon one which was quite impossible.

In any case, Buonaparte felt the strategic importance of the position on the Saale so much, that he did not venture to pass it by, but determined on a passage of the Saale in sight of the enemy.

By what we have now said we think we have sufficiently specified the relations between the defence and the attack when a decisive course of action is intended, and we believe we have shown also the threads to which, according to their situation and connection, the different subjects of the plan of defence attach themselves. To go through the different arrangements more in detail does not come within our views, for that would lead us into a boundless field of particular cases. When a general has laid down for his direction a distinct point, he will see how far it agrees with geographical, statistical, and political circumstances, the material and personal relations of his own army and that of the enemy, and how the one or the other may require that his plans should be modified in carrying them into effect.

But in order more distinctly to connect and look closer at the gradations in the defence specified in the chapter on the different kinds of defence, we shall here lay before our readers what seems to us most important, in relation to the same generally.

1. Reasons for marching against the enemy with a view to an offensive battle, may be as follows:—

(a) If we know that the enemy is advancing with his forces very much divided, and therefore we have reason to expect a victory, although we are, upon the whole, much weaker.

But such an advance on the part of the assailant is in itself very improbable, and consequently, unless we know of it upon certain information, the plan is not good; for to reckon upon it, and rest all our hopes on it through a mere supposition, and without sufficient motive, leads generally to a very dangerous situation. We do not, then, find things as we expected; we are obliged to give up the offensive battle, we are not prepared to fight on the defensive, we are obliged to commence with a retreat against our will, and leave almost everything to chance.

This is very much what occurred in the defence, conducted by the army under Dohna against the Russians, in the campaign of 1759, and which, under General Wedel, ended in the unfortunate battle of Züllichau.

This measure shortens matters so much that plan-makers are only too ready to propose it, without taking much trouble to inquire how far the hypothesis on which it rests is well founded.

(b) If we are generally in sufficient strength for battle, and—

(c) If a blundering, irresolute adversary specially invites an attack.

In this case the effect of surprise may be worth more than any assistance furnished by the ground through a good position. It is the real essence of good generalship thus to bring into play the power of the moral forces;—but theory can never say loud enough nor often enough there must be an objective foundation for these suppositions; without such foundation to be always talking of surprises and the superiority of novel or unusual modes of attack, and thereon to found plans, considerations, criticisms, is acting without any grounds, and is altogether objectionable.

(d) When the nature of our army makes it specially suited for the offensive.

It was certainly not a visionary or false idea when Frederick the Great conceived that in his mobile, courageous army, full of confidence in him, obedient by habit, trained to precision, animated and elevated by pride, and with its perfection in the oblique attack, he possessed an instrument which, in his firm and daring hand, was much more suited to attack than defence; all these qualities were wanting in his opponents, and in this respect, therefore, he had the most decided superiority; to make use of this was worth more to him, in most cases, than to take to his assistance entrenchments and obstacles of ground.—But such a superiority will always be rare; a well-trained army, thoroughly practised in great movements, has only part of the above advantages. If Frederick the Great maintained that the Prussian army was particularly adapted for attack—and this has been incessantly repeated since his time—still we should not attach too much weight to any such saying; in most cases in war we feel more exhilarated, more courageous when acting offensively than defensively: but this is a feeling which all troops have in common, and there is hardly an army respecting which its generals and leaders have not made the same assertion (as Frederick). We must, therefore, not too readily rely on an appearance of superiority, and through that neglect real advantages.

A very natural and weighty reason for resorting to an offensive battle may be the composition of the army as regards the three arms, for instance, a numerous cavalry and little artillery.

We continue the enumeration of reasons.

(e) When we can nowhere find a good position.

(f) When we must hasten with the decision.

(g) Lastly, the combined influence of several or all of these reasons.

2. The waiting for the enemy in a locality where it is intended to attack him (Minden, 1759) naturally proceeds from—

a, there being no such disproportion of force to our disadvantage as to make it necessary to seek a strong position and strengthen it by entrenchments.

b, a locality having been found particularly adapted to the purpose. The properties which determine this belong to tactics; we shall only observe that these properties chiefly consist in an easy approach for the defender from his side, and in all kinds of obstacles on the side next to the enemy.

3. A position will be taken with the express intention of there waiting the attack of the enemy—

a. If the disproportion of forces compels us to seek cover from natural obstacles or behind field-works.

b. When the country affords an excellent position for our purpose.

The two modes of defence, 2 and 3, will come more into consideration according as we do not seek the decision itself, but content ourselves with a negative result, and have reason to think that our opponent is wavering and irresolute, and that he will in the end fail to carry out his plans.

4. An entrenched unassailable camp only fulfils the object—

a. If it is situated at an extremely important strategic point.

The character of such a position consists in this, that we cannot be driven out of it; the enemy is therefore obliged to try some other means, that is, to pursue his object without touching this camp, or to blockade it and reduce it by starvation: if it is impossible for him to do this, then the strategic qualities of the position must be very great.

b. If we have reason to expect aid from abroad.

Such was the case with the Saxon army in its position at Pirna. Notwithstanding all that has been said against the measure on account of the ill-success which attended it in this instance, it is perfectly certain that 17,000 Saxons could never have been able to neutralise 40,000 Prussians in any other way. If the Austrians were unable to make better use of the superiority obtained at Lowositz, that only shows the badness of their whole method of war, as well as of their whole military organisation; and there cannot be a doubt that if the Saxons instead of taking post in the camp at Pirna had retired into Bohemia, Frederick the Great would have driven both Austrians and Saxons beyond Prague, and taken that place in the same campaign. Whoever does not admit the value of this advantage, and limits his consideration to the capture of the whole Saxon army, shows himself incapable of making a calculation of all the circumstances in a case of this kind, and without calculation no certain deduction can be obtained.

But as the cases a and b very rarely occur, therefore, the entrenched camp is a measure which requires to be well considered, and which is very seldom suitable in practice. The hope of inspiring the enemy with respect by such a camp, and thus reducing him to a state of complete inactivity, is attended with too much danger, namely, with the danger of being obliged to fight without the possibility of retreat. If Frederick the Great gained his object in this way at Bunzelwitz, we must admire the correct judgment he formed of his adversary, but we must certainly also lay more stress than usual on the resources which he would have found at the last moment to clear a road for the remnants of his army, and also on the irresponsibility of a king.

5. If there is one or if there are several fortresses near the frontier, then the great question arises, whether the defender should seek an action before or behind them. The latter recommends itself—

a, by the superiority of the enemy in numbers, which forces us to break his power before coming to a final struggle.

b, by these fortresses being near, so that the sacrifice of territory is not greater than we are compelled to make.

c, by the fitness of the fortresses for defence.

One principal use of fortresses is unquestionably, or should be, to break the enemy’s force in his advance and to weaken considerably that portion which we intend to bring to an engagement. If we so seldom see this use made of fortresses, that proceeds from the cases in which a decisive battle is sought for by one of the opposing parties being very rare. But that is the only kind of case which we treat of here. We therefore look upon it as a principle equally simple and important in all cases in which the defender has one or more fortresses near him, that he should keep them before him, and give the decisive battle behind them. We admit that a battle lost within the line of our fortresses will compel us to retreat further into the interior of the country than one lost on the other side, tactical results in both cases being the same, although the causes of the difference have their origin rather in the imagination than in real things; neither do we forget that a battle may be given beyond the fortresses in a well chosen position, whilst inside them the battle in most cases must be an offensive one, particularly if the enemy is laying siege to a fortress which is in danger of being lost; but what signify these nice shades of distinction, as compared to the advantage that, in the decisive battle, we meet the enemy weakened by a fourth or a third of his force, perhaps one half if there are many fortresses?

We think, therefore, that in all cases of an inevitable decision, whether sought for by the offensive or the defensive, and that the latter is not tolerably sure of a victory, or if the nature of the country does not offer some most decisive reason to give battle in a position further forward—in all these cases we say when a fortress is situated near at hand and capable of defence, the defender should by all means withdraw at once behind it, and let the decision take place on this side, consequently with its co-operation. If he takes up his position so close to the fortress that the assailant can neither form the siege of nor blockade the place without first driving him off, he places the assailant under the necessity of attacking him, the defender, in his position. To us, therefore, of all defensive measures in a critical situation, none appears so simple and efficacious as the choice of a good position near to and behind a strong fortress.

At the same time, the question would wear a different aspect if the fortress was situated far back; for then it would be necessary to abandon a considerable part of our theatre of war, a sacrifice which, as we know, should not be made unless in a case of great urgency. In such a case the measure would bear more resemblance to a retreat into the interior of the country.

Another condition is, the fitness of the place for defence. It is well known that there are fortified places, especially large ones, which are not fit to be brought into contact with an enemy’s army, because they could not resist the sudden assault of a powerful force. In this case, our position must at all events be so close behind that we could support the garrison.

Lastly, the retreat into the interior of the country is only a natural resource under the following circumstances:—

a, when owing to the physical and moral relation in which we stand as respects the enemy, the idea of a successful resistance on the frontier or near it cannot be entertained.

b, when it is a principal object to gain time.

c, when there are peculiarities in the country which are favourable to the measure, a subject on which we have already treated in the twenty-fifth chapter.

We thus close the chapter on the defence of a theatre of war if a decisive solution is sought for by one or other party, and is therefore inevitable. But it must be particularly borne in mind, that events in war do not exhibit themselves in such a pure abstract form, and that therefore, if our maxims and arguments should be used in reasoning on actual war, our thirtieth chapter should also be kept in view, and we must suppose the general, in the majority of cases, as placed between two tendencies, urged more towards one or the other, according to circumstances.

XXIX. Defence of a Theatre of War (continued) Successive Resistance

We have proved, in the twelfth and thirteenth chapters, that in strategy a successive resistance is inconsistent with the nature of the thing, and that all forces available should be used simultaneously.

As regards forces which are moveable, this requires no further demonstration; but when we look at the seat of war itself, with its fortresses, the natural divisions of the ground, and even the extent of its surface as being also elements of war, then, these being immovable, we can only either bring them gradually into use, or we must at once place ourselves so far back, that all agencies of this kind which are to be brought into activity are in our front. Then everything which can contribute to weaken the enemy in the territory which he has occupied, comes at once into activity, for the assailant must at least blockade the defender’s fortresses, he must keep the country in subjection by garrisons and other posts, he has long marches to make, and everything he requires must be brought from a distance, etc. All these agencies commence to work, whether the assailant makes his advance before or after a decision, but in the former case their influence is somewhat greater. From this, therefore, it follows, that if the defender chooses to transfer his decision to a point further back, he has thus the means of bringing at once into play all these immovable elements of military force.

On the other hand, it is clear that this transfer of the solution (on the part of the defender) does not alter the extent of the influence of a victory which the assailant gains. In treating of the attack, we shall examine more closely the extent of the influence of a victory; here we shall only observe that it reaches to the exhaustion of the superiority, that is, the resultant of the physical and moral relations. Now this superiority exhausts itself in the first place by the duties required from the forces on the theatre of war, and secondly by losses in combats; the diminution of force arising from these two causes cannot be essentially altered, whether the combats take place at the commencement or at the end, near the frontier, or further towards the interior of the country (vom oder hinten). We think, for example, that a victory gained by Buonaparte over the Russians at Wilna, 1812, would have carried him just as far as that of Borodino—assuming that it was equally great—and that a victory at Moscow would not have carried him any further; Moscow was, in either case, the limit of this sphere of victory. Indeed, it cannot be doubted for a moment that a decisive battle on the frontier (for other reasons) would have produced much greater results through victory, and then, perhaps, the sphere of its influence would have been wider. Therefore, in this view, also, the transfer of the decision to a point further back is not necessary for the defence.

In the chapter on the various means of resistance, that method of delaying the decision, which may be regarded as an extreme form, was brought before us under the name of retreat into the interior, and as a particular method of defence, in which the object is rather that the assailant should wear himself out, than that he should be destroyed by the sword on the field of battle. But it is only when such an intention predominates that the delaying of the decisive battle can be regarded as a peculiar method of resistance; for otherwise it is evident that an infinite number of gradations may be conceived in this method, and that these may be combined with all other means of defence. We therefore look upon the greater or less co-operation of the theatre of war, not as a special form of defence, but as nothing more than a discretionary introduction into the defence of the immovable means of resistance, just according as circumstances and the nature of the situation may appear to require.

But now, if the defender does not think he requires any assistance from these immovable forces for his purposed decision, or if the further sacrifice connected with the use of them is too great, then they are kept in reserve for the future, and form a sort of succession of reinforcements, which perhaps ensure the possibility of keeping the moveable forces in such a condition that they will be able to follow up the first favourable decision with a second, or perhaps in the same manner even with a third, that is to say, in this manner a successive application of his forces becomes possible.

If the defender loses a battle on the frontier, which does not amount to a complete defeat, we may very well imagine that, by placing himself behind the nearest fortress, he will then be in a condition to accept battle again; indeed, if he is only dealing with an opponent who has not much resolution, then, perhaps, some considerable obstacle of ground will be quite sufficient as a means of stopping the enemy.

There is, therefore, in strategy, in the use of the theatre of war as well as in everything else, an economy of force; the less one can make suffice the better: but there must be sufficient, and here, as well as in commerce, there is something to be thought of besides mere niggardliness.

But in order to prevent a great misconception, we must draw attention to this, that the subject of our present consideration is not how much resistance an army can offer, or the enterprises which it can undertake after a lost battle, but only the result which we can promise ourselves beforehand from this second act in our defence; consequently, how high we can estimate it in our plan. Here there is only one point almost which the defender has to look to, which is the character and the situation of his opponent. An adversary weak in character, with little self-confidence, without noble ambition, placed under great restrictions, will content himself, in case he is successful, with a moderate advantage, and timidly hold back at every fresh offer of a decision which the defender ventures to make. In this case the defender may count upon the beneficial use of all the means of resistance of his theatre of war in succession, in constantly fresh, although in themselves small, combats, in which the prospect always brightens of an ultimate decision in his favour.

But who does not feel that we are now on the road to campaigns devoid of decision, which are much more the field of a successive application of force. Of these we shall speak in the following chapter.