On War
Clausewitz (1827)

Chapter VII. Decision of the Combat

No battle is decided in a single moment, although in every battle there arise moments of crisis, on which the result depends. The loss of a battle is, therefore, a gradual falling of the scale. But there is in every combat a point of time

[*] Under the then existing conditions of armament understood. This point is of supreme importance, as practically the whole conduct of a great battle depends on a correct solution of this question--viz., How long can a given command prolong its resistance? If this is incorrectly answered in practice--the whole manoeuvre depending on it may collapse--e.g., Kouroupatkin at Liao-Yang, September 1904.

when it may be regarded as decided, in such a way that the renewal of the fight would be a new battle, not a continuation of the old one. To have a clear notion on this point of time, is very important, in order to be able to decide whether, with the prompt assistance of reinforcements, the combat can again be resumed with advantage.

Often in combats which are beyond restoration new forces are sacrificed in vain; often through neglect the decision has not been seized when it might easily have been secured. Here are two examples, which could not be more to the point:

When the Prince of Hohenlohe, in 1806, at Jena, [October 14, 1806] with 35,000 men opposed to from 60,000 to 70,000, under Buonaparte, had accepted battle, and lost it--but lost it in such a way that the 35,000 might be regarded as dissolved--General Ruchel undertook to renew the fight with about 12,000; the consequence was that in a moment his force was scattered in like manner.

On the other hand, on the same day at Auerstadt, the Prussians maintained a combat with 25,000, against Davoust, who had 28,000, until mid-day, without success, it is true, but still without the force being reduced to a state of dissolution without even greater loss than the enemy, who was very deficient in cavalry;--but they neglected to use the reserve of 18,000, under General Kalkreuth, to restore the battle which, under these circumstances, it would have been impossible to lose.

Each combat is a whole in which the partial combats combine themselves into one total result. In this total result lies the decision of the combat. This success need not be exactly a victory such as we have denoted in the sixth chapter, for often the preparations for that have not been made, often there is no opportunity if the enemy gives way too soon, and in most cases the decision, even when the resistance has been obstinate, takes place before such a degree of success is attained as would completely satisfy the idea of a victory.

We therefore ask, Which is commonly the moment of the decision, that is to say, that moment when a fresh, effective, of course not disproportionate, force, can no longer turn a disadvantageous battle?

If we pass over false attacks, which in accordance with their nature are properly without decision, then

1. If the possession of a movable object was the object of the combat, the loss of the same is always the decision.

2. If the possession of ground was the object of the combat, then the decision generally lies in its loss. Still not always, only if this ground is of peculiar strength, ground which is easy to pass over, however important it may be in other respects, can be re-taken without much danger.

3. But in all other cases, when these two circumstances have not already decided the combat, therefore, particularly in case the destruction of the enemy’s force is the principal object, the decision is reached at that moment when the conqueror ceases to feel himself in a state of disintegration, that is, of unserviceableness to a certain extent, when therefore, there is no further advantage in using the successive efforts spoken of in the twelfth chapter of the third book. On this ground we have given the strategic unity of the battle its place here.

A battle, therefore, in which the assailant has not lost his condition of order and perfect efficiency at all, or, at least, only in a small part of his force, whilst the opposing forces are, more or less, disorganised throughout, is also not to be retrieved; and just as little if the enemy has recovered his efficiency.

The smaller, therefore, that part of a force is which has really been engaged, the greater that portion which as reserve has contributed to the result only by its presence. so much the less will any new force of the enemy wrest again the victory from our hands, and that Commander who carries out to the furthest with his Army the principle of conducting the combat with the greatest economy of forces, and making the most of the moral effect of strong reserves, goes the surest way to victory. We must allow that the French, in modern times, especially when led by Buonaparte, have shown a thorough mastery in this.

Further, the moment when the crisis-stage of the combat ceases with the conqueror, and his original state of order is restored, takes place sooner the smaller the unit he controls. A picket of cavalry pursuing an enemy at full gallop will in a few minutes resume its proper order, and the crisis ceases. A whole regiment of cavalry requires a longer time. It lasts still longer with infantry, if extended in single lines of skirmishers, and longer again with Divisions of all arms, when it happens by chance that one part has taken one direction and another part another direction, and the combat has therefore caused a loss of the order of formation, which usually becomes still worse from no part knowing exactly where the other is. Thus, therefore, the point of time when the conqueror has collected the instruments he has been using, and which are mixed up and partly out of order, the moment when he has in some measure rearranged them and put them in their proper places, and thus brought the battle-workshop into a little order, this moment, we say, is always later, the greater the total force.

Again, this moment comes later if night overtakes the conqueror in the crisis, and, lastly, it comes later still if the country is broken and thickly wooded. But with regard to these two points, we must observe that night is also a great means of protection, and it is only seldom that circumstances favour the expectation of a successful result from a night attack, as on March 10, 1814, at Laon, [The celebrated charge at night upon Marmont’s Corps] where York against Marmont gives us an example completely in place here. In the same way a wooded and broken country will afford protection against a reaction to those who are engaged in the long crisis of victory. Both, therefore, the night as well as the wooded and broken country are obstacles which make the renewal of the same battle more difficult instead of facilitating it.

Hitherto, we have considered assistance arriving for the losing side as a mere increase of force, therefore, as a reinforcement coming up directly from the rear, which is the most usual case. But the case is quite different if these fresh forces come upon the enemy in flank or rear.

On the effect of flank or rear attacks so far as they belong to Strategy, we shall speak in another place: such a one as we have here in view, intended for the restoration of the combat, belongs chiefly to tactics, and is only mentioned because we are here speaking of tactical results, our ideas, therefore, must trench upon the province of tactics.

By directing a force against the enemy’s flank and rear its efficacy may be much intensified; but this is so far from being a necessary result always that the efficacy may, on the other hand, be just as much weakened. The circumstances under which the combat has taken place decide upon this part of the plan as well as upon every other, without our being able to enter thereupon here. But, at the same time, there are in it two things of importance for our subject: first, flank and rear attacks have, as A rule, A more favourable effect on the consequences of the decision than upon the decision itself. Now as concerns the retrieving a battle, the first thing to be arrived at above all is a favourable decision and not magnitude of success. In this view one would therefore think that a force which comes to re-establish our combat is of less assistance if it falls upon the enemy in flank and rear, therefore separated from us, than if it joins itself to us directly; certainly, cases are not wanting where it is so, but we must say that the majority are on the other side, and they are so on account of the second point which is here important to us.

This second point is the moral effect of the surprise, which, as A rule, A reinforcement coming up to re-establish A combat has generally in its favour. Now the effect of a surprise is always heightened if it takes place in the flank or rear, and an enemy completely engaged in the crisis of victory in his extended and scattered order, is less in a state to counteract it. Who does not feel that an attack in flank or rear, which at the commencement of the battle, when the forces are concentrated and prepared for such an event would be of little importance, gains quite another weight in the last moment of the combat.

We must, therefore, at once admit that in most cases a reinforcement coming up on the flank or rear of the enemy will be more efficacious, will be like the same weight at the end of a longer lever, and therefore that under these circumstances, we may undertake to restore the battle with the same force which employed in a direct attack would be quite insufficient. Here results almost defy calculation, because the moral forces gain completely the ascendency. This is therefore the right field for boldness and daring.

The eye must, therefore, be directed on all these objects, all these moments of co-operating forces must be taken into consideration, when we have to decide in doubtful cases whether or not it is still possible to restore a combat which has taken an unfavourable turn.

If the combat is to be regarded as not yet ended, then the new contest which is opened by the arrival of assistance fuses into the former; therefore they flow together into one common result, and the first disadvantage vanishes completely out of the calculation. But this is not the case if the combat was already decided; then there are two results separate from each other. Now if the assistance which arrives is only of a relative strength, that is, if it is not in itself alone a match for the enemy, then a favourable result is hardly to be expected from this second combat: but if it is so strong that it can undertake the second combat without regard to the first, then it may be able by a favourable issue to compensate or even overbalance the first combat, but never to make it disappear altogether from the account.

At the battle of Kunersdorf, [August 12, 1759] Frederick the Great at the first onset carried the left of the Russian position, and took seventy pieces of artillery; at the end of the battle both were lost again, and the whole result of the first combat was wiped out of the account. Had it been possible to stop at the first success, and to put off the second part of the battle to the coming day, then, even if the King had lost it, the advantages of the first would always have been a set off to the second.

But when a battle proceeding disadvantageously is arrested and turned before its conclusion, its minus result on our side not only disappears from the account, but also becomes the foundation of a greater victory. If, for instance, we picture to ourselves exactly the tactical course of the battle, we may easily see that until it is finally concluded all successes in partial combats are only decisions in suspense, which by the capital decision may not only be destroyed, but changed into the opposite. The more our forces have suffered, the more the enemy will have expended on his side; the greater, therefore, will be the crisis for the enemy, and the more the superiority of our fresh troops will tell. If now the total result turns in our favour, if we wrest from the enemy the field of battle and recover all the trophies again, then all the forces which he has sacrificed in obtaining them become sheer gain for us, and our former defeat becomes a stepping-stone to a greater triumph. The most brilliant feats which with victory the enemy would have so highly prized that the loss of forces which they cost would have been disregarded, leave nothing now behind but regret at the sacrifice entailed. Such is the alteration which the magic of victory and the curse of defeat produces in the specific weight of the same elements.

Therefore, even if we are decidedly superior in strength, and are able to repay the enemy his victory by a greater still, it is always better to forestall the conclusion of a disadvantageous combat, if it is of proportionate importance, so as to turn its course rather than to deliver a second battle.

Field-Marshal Daun attempted in the year 1760 to come to the assistance of General Laudon at Leignitz, whilst the battle lasted; but when he failed, he did not attack the King next day, although he did not want for means to do so.

For these reasons serious combats of advance guards which precede a battle are to be looked upon only as necessary evils, and when not necessary they are to be avoided. [This, however, was not Napoleon’s view. A vigorous attack of his advance guard he held to be necessary always, to fix the enemy’s attention and “paralyse his independent will-power.” It was the failure to make this point which, in August 1870, led von Moltke repeatedly into the very jaws of defeat, from which only the lethargy of Bazaine on the one hand and the initiative of his subordinates, notably of von Alvensleben, rescued him. This is the essence of the new Strategic Doctrine of the French General Staff. See the works of Bonnal, Foch, &.--editor]

We have still another conclusion to examine.

If on a regular pitched battle, the decision has gone against one, this does not constitute a motive for determining on a new one. The determination for this new one must proceed from other relations. This conclusion, however, is opposed by a moral force, which we must take into account: it is the feeling of rage and revenge. From the oldest Field-Marshal to the youngest drummer-boy this feeling is general, and, therefore, troops are never in better spirits for fighting than when they have to wipe out a stain. This is, however, only on the supposition that the beaten portion is not too great in proportion to the whole, because otherwise the above feeling is lost in that of powerlessness.

There is therefore a very natural tendency to use this moral force to repair the disaster on the spot, and on that account chiefly to seek another battle if other circumstances permit. It then lies in the nature of the case that this second battle must be an offensive one.

In the catalogue of battles of second-rate importance there are many examples to be found of such retaliatory battles; but great battles have generally too many other determining causes to be brought on by this weaker motive.

Such a feeling must undoubtedly have led the noble Bluecher with his third Corps to the field of battle on February 14, 1814, when the other two had been beaten three days before at Montmirail. Had he known that he would have come upon Buonaparte in person, then, naturally, preponderating reasons would have determined him to put off his revenge to another day: but he hoped to revenge himself on Marmont, and instead of gaining the reward of his desire for honourable satisfaction, he suffered the penalty of his erroneous calculation.

On the duration of the combat and the moment of its decision depend the distances from each other at which those masses should be placed which are intended to fight in conjunction with each other. This disposition would be a tactical arrangement in so far as it relates to one and the same battle; it can, however, only be regarded as such, provided the position of the troops is so compact that two separate combats cannot be imagined, and consequently that the space which the whole occupies can be regarded strategically as a mere point. But in War, cases frequently occur where even those forces intended to fight in unison must be so far separated from each other that while their union for one common combat certainly remains the principal object, still the occurrence of separate combats remains possible. Such a disposition is therefore strategic.

Dispositions of this kind are: marches in separate masses and columns, the formation of advance guards, and flanking columns, also the grouping of reserves intended to serve as supports for more than one strategic point; the concentration of several Corps from widely extended cantonments, &. &. We can see that the necessity for these arrangements may constantly arise, and may consider them something like the small change in the strategic economy, whilst the capital battles, and all that rank with them are the gold and silver pieces.