Carl von Clausewitz

[Table of Contents]

BOOK 7  •  CHAPTER 19

Attack on the Enemy's Army in its Cantonments

WE have not treated of this subject in the defence, because a line of cantonments is not to be regarded as a defensive means, but as a mere existence of the army in a state which implies little readiness for battle. In respect to this readiness for battle, we therefore did not go beyond what we required to say in connection with this condition of an army in the 13th chapter of the 5th book.

But here, in considering the attack, we have to think of an enemy's army in cantonments in all respects as a special object; for, in the first place, such an attack is of a very peculiar kind in itself; and, in the next place, it may be considered as a strategic means of particular efficacy. Here we have before us, therefore, not the question of an onslaught on a single cantonment or a small corps dispersed amongst a few villages, as the arrangements for that are entirely of a tactical nature, but of the attack of a large army, distributed in cantonments more or less extensive; an attack in which the object is not the mere surprise of a single cantonment, but to prevent the assembly of the army.

The attack on an enemy's army in cantonments is therefore the surprise of an army not assembled. If this surprise succeeds fully, then the enemy's army is prevented from reaching its appointed place of assembly, and, therefore, compelled to choose another more to the rear; as this change of the point of assembly to the rear in a state of such emergency can seldom be effected in less than a day's march, but generally will require several days, the loss of ground which this occasions is by no means an insignificant loss; and this is the first advantage gained by the assailant.

But now, this surprise which is in connection with the general relations, may certainly at the same time, in its commencement, be an onslaught on some of the enemy's single cantonments, not certainly upon all, or upon a great many, because that would suppose a scattering of the attacking army to an extent which could never be advisable. Therefore, only the most advanced quarters, only those which lie in the direction of the attacking columns, can be surprised, and even this will seldom happen to many of them, as large forces cannot easily approach unobserved. However, this element of the attack is by no means to be disregarded; and we reckon the advantages which may be thus obtained, as the second advantage of the surprise.

A third advantage consists in the minor combats forced upon the enemy in which his losses will be considerable. A great body of troops does not assemble itself at once by single battalions at the spot appointed for the general concentration of the army, but usually forms itself by brigades, divisions, or corps, in the first place, and these masses cannot then hasten at full speed to the rendezvous; in case of meeting with an enemy's column in their course, they are obliged to engage in a combat; now, they may certainly come off victorious in the same, particularly if the enemy's attacking column is not of sufficient strength, but in conquering, they lose time, and, in most cases, as may be easily conceived, a corps, under such circumstances, and in the general tendency to gain a point which lies to the rear, will not make any beneficial use of its victory. On the other hand, they may be beaten, and that is the most probable issue in itself, because they have not time to organise a good resistance. We may, therefore, very well suppose that in an attack well planned and executed, the assailant through these partial combats will gather up a considerable number of trophies, which become a principal point in the general result.

Lastly, the fourth advantage, and the keystone of the whole, is a certain momentary disorganisation and discouragement on the side of the enemy, which, when the force is at last assembled, seldom allows of its being immediately brought into action, and generally obliges the party attacked to abandon still more ground to his assailant, and to make a change generally in his plan of operations.

Such are the proper results of a successful surprise of the enemy in cantonments, that is, of one in which the enemy is prevented from assembling his army without loss at the point fixed in his plan. But by the nature of the case, success has many degrees; and, therefore, the results may be very great in one case, and hardly worth mentioning in another. But even when, through the complete success of the enterprise, these results are considerable, they will seldom bear comparison with the gain of a great battle, partly because, in the first place, the trophies are seldom as great, and in the next, the moral impression never strikes so deep.

This general result must always be kept in view, that we may not promise ourselves more from an enterprise of this kind than it can give. Many hold it to be the non plus ultra of offensive activity; but it is not so by any means, as we may see from this analysis, as well as from military history.

One of the most brilliant surprises in history, is that made by the Duke of Lorraine in 1643, on the cantonments of the French, under General Ranzan, at Duttlingen. The corps was 16,000 men, and they lost the General commanding, and 7,000 men; it was a complete defeat. The want of outposts was the cause of the disaster.

The surprise of Turenne at Mergentheim (Mariendal, as the French call it,) in 1644, is in like manner to be regarded as equal to a defeat in its effects, for he lost 3,000 men out of 8,000, which was principally owing to his having been led into making an untimely stand after he got his men assembled. Such results we cannot, therefore, often reckon upon; it was rather the result of an ill-judged action than of the surprise, properly speaking, for Turenne might easily have avoided the action, and have rallied his troops upon those in more distant quarters.

A third noted surprise is that which Turenne made on the Allies under the great Elector, the Imperial General Bournonville and the Duke of Lorraine, in Alsace, in the year 1674. The trophies were very small, the loss of the Allies did not exceed 2,000 or 3,000 men, which could not decide the fate of a force of 50,000; but the Allies considered that they could not venture to make any further resistance in Alsace, and retired across the Rhine again. This strategic result was all that Turenne wanted, but we must not look for the causes of it entirely in the surprise. Turenne surprised the plans of his opponents more than the troops themselves; the want of unanimity amongst the allied generals and the proximity of the Rhine did the rest. This event altogether deserves a closer examination, as it is generally viewed in a wrong light.

In 1741, Neipperg surprised Frederick the Great in his quarters; the whole of the result was that the king was obliged to fight the battle of Mollwitz before he had collected all his forces, and with a change of front.

In 1745, Frederick the Great surprised the Duke of Lorraine in his cantonments in Lusatia; the chief success was through the real surprise of one of the most important quarters, that of Hennersdorf, by which the Austrians suffered a loss of 2,000 men; the general result was that the Duke of Lorraine retreated to Bohemia by Upper Lusatia, but that did not at all prevent his returning into Saxony by the left bank of the Elbe, so that without the battle of Kesselsdorf, there would have been no important result.

1758. The Duke Ferdinand surprised the French quarters; the immediate result was that the French lost some thousands of men, and were obliged to take up a position behind the Aller. The moral effect may have been of more importance, and may have had some influence on the subsequent evacuation of Westphalia.

If from these different examples we seek for a conclusion as to the efficacy of this kind of attack, then only the two first can be put in comparison with a battle gained. But the corps were only small, and the want of outposts in the system of war in those days was a circumstance greatly in favour of these enterprises. Although the four other cases must be reckoned completely successful enterprises, it is plain that not one of them is to be compared with a battle gained as respects its result. The general result could not have taken place in any of them except with an adversary weak in will and character, and therefore it did not take place at all in the case of 1741.

In 1806 the Prussian army contemplated surprising the French in this manner in Franconia. The case promised well for a satisfactory result. Buonaparte was not present, the French corps were in widely extended cantonments; under these circumstances, the Prussian army, acting with great resolution and activity, might very well reckon on driving the French back across the Rhine, with more or less loss. But this was also all; if they reckoned upon more, for instance, on following up their advantages beyond the Rhine, or on gaining such a moral ascendancy, that the French would not again venture to appear on the right bank of the river in the same campaign, such an expectation had no sufficient grounds whatever.

In the beginning of August, 1812, the Russians from Smolensk meditated falling upon the cantonments of the French when Napoleon halted his army in the neighbourhood of Witepsk. But they wanted courage to carry out the enterprise; and it was fortunate for them they did; for as the French commander with his centre was not only more than twice the strength of their centre, but also in himself the most resolute commander that ever lived, as further, the loss of a few miles of ground would have decided nothing, and there was no natural obstacle in any feature of the country near enough up to which they might pursue their success, and by that means, in some measure make it certain, and lastly, as the war of the year 1812 was not in any way a campaign of that kind, which draws itself in a languid way to a conclusion, but the serious plan of an assailant who had made up his mind to conquer his opponent completely,—therefore the trifling results to be expected from a surprise of the enemy in his quarters, appear nothing else than utterly disproportionate to the solution of the problem, they could not justify a hope of making good by their means the great inequality of forces and other relations. But this scheme serves to show how a confused idea of the effect of this means may lead to an entirely false application of the same.

What has been hitherto said, places the subject in the light of a strategic means. But it lies in its nature that its execution also is not purely tactical, but in part belongs again to strategy so far, particularly that such an attack is generally made on a front of considerable width, and the army which carries it out can, and generally will, come to blows before it is concentrated, so that the whole is an agglomeration of partial combats. We must now add a few words on the most natural organisation of such an attack.

The first condition is:—