On War
Clausewitz (1827)

Chapter IX. The Battle


[Clausewitz still uses the word “die Hauptschlacht” but modern usage employs only the word “die Schlacht” to designate the decisive act of a whole campaign--encounters arising from the collision or troops marching towards the strategic culmination of each portion or the campaign are spoken of either as “Treffen,” i.e., “engagements” or “Gefecht,” i.e., “combat” or “action.” Thus technically, Gravelotte was a “Schlacht,” i.e., “battle,” but Spicheren, Woerth, Borny, even Vionville were only “Treffen."]

Its Decision

What is a battle? A conflict of the main body, but not an unimportant one about a secondary object, not a mere attempt which is given up when we see betimes that our object is hardly within our reach: it is a conflict waged with all our forces for the attainment of a decisive victory.

Minor objects may also be mixed up with the principal object, and it will take many different tones of colour from the circumstances out of which it originates, for a battle belongs also to a greater whole of which it is only a part, but because the essence of War is conflict, and the battle is the conflict of the main Armies, it is always to be regarded as the real centre of gravity of the War, and therefore its distinguishing character is, that unlike all other encounters, it is arranged for, and undertaken with the sole purpose of obtaining a decisive victory.

This has an influence on the manner of its decision, on the effect of the victory contained in it, and determines the value which theory is to assign to it as A means to an end.

On that account we make it the subject of our special consideration, and at this stage before we enter upon the special ends which may be bound up with it, but which do not essentially alter its character if it really deserves to be termed a battle.

If a battle takes place principally on its own account, the elements of its decision must be contained in itself; in other words, victory must be striven for as long as a possibility or hope remains. It must not, therefore, be given up on account of secondary circumstances, but only and alone in the event of the forces appearing completely insufficient.

Now how is that precise moment to be described?

If a certain artificial formation and cohesion of an Army is the principal condition under which the bravery of the troops can gain a victory, as was the case during a great part of the period of the modern Art of War, then the breaking up of this formation is the decision. A beaten wing which is put out of joint decides the fate of all that was connected with it. If as was the case at another time the essence of the defence consists in an intimate alliance of the Army with the ground on which it fights and its obstacles, so that Army and position are only one, then the conquest of an essential point in this position is the decision. It is said the key of the position is lost, it cannot therefore be defended any further; the battle cannot be continued. In both cases the beaten Armies are very much like the broken strings of an instrument which cannot do their work.

That geometrical as well as this geographical principle which had a tendency to place an Army in a state of crystallising tension which did not allow of the available powers being made use of up to the last man, have at least so far lost their influence that they no longer predominate. Armies are still led into battle in a certain order, but that order is no longer of decisive importance; obstacles of ground are also still turned to account to strengthen a position, but they are no longer the only support.

We attempted in the second chapter of this book to take a general view of the nature of the modern battle. According to our conception of it, the order of battle is only a disposition of the forces suitable to the convenient use of them, and the course of the battle a mutual slow wearing away of these forces upon one another, to see which will have soonest exhausted his adversary.

The resolution therefore to give up the fight arises, in a battle more than in any other combat, from the relation of the fresh reserves remaining available; for only these still retain all their moral vigour, and the cinders of the battered, knocked-about battalions, already burnt out in the destroying element, must not be placed on a level with them; also lost ground as we have elsewhere said, is a standard of lost moral force; it therefore comes also into account, but more as a sign of loss suffered than for the loss itself, and the number of fresh reserves is always the chief point to be looked at by both Commanders.

In general, an action inclines in one direction from the very commencement, but in a manner little observable. This direction is also frequently given in a very decided manner by the arrangements which have been made previously, and then it shows a want of discernment in that General who commences battle under these unfavourable circumstances without being aware of them. Even when this does not occur it lies in the nature of things that the course of a battle resembles rather a slow disturbance of equilibrium which commences soon, but as we have said almost imperceptibly at first, and then with each moment of time becomes stronger and more visible, than an oscillating to and fro, as those who are misled by mendacious descriptions usually suppose.

But whether it happens that the balance is for a long time little disturbed, or that even after it has been lost on one side it rights itself again, and is then lost on the other side, it is certain at all events that in most instances the defeated General foresees his fate long before he retreats, and that cases in which some critical event acts with unexpected force upon the course of the whole have their existence mostly in the colouring with which every one depicts his lost battle.

We can only here appeal to the decision of unprejudiced men of experience, who will, we are sure, assent to what we have said, and answer for us to such of our readers as do not know War from their own experience. To develop the necessity of this course from the nature of the thing would lead us too far into the province of tactics, to which this branch of the subject belongs; we are here only concerned with its results.

If we say that the defeated General foresees the unfavourable result usually some time before he makes up his mind to give up the battle, we admit that there are also instances to the contrary, because otherwise we should maintain a proposition contradictory in itself. If at the moment of each decisive tendency of a battle it should be considered as lost, then also no further forces should be used to give it a turn, and consequently this decisive tendency could not precede the retreat by any length of time. Certainly there are instances of battles which after having taken a decided turn to one side have still ended in favour of the other; but they are rare, not usual; these exceptional cases, however, are reckoned upon by every General against whom fortune declares itself, and he must reckon upon them as long as there remains a possibility of a turn of fortune. He hopes by stronger efforts, by raising the remaining moral forces, by surpassing himself, or also by some fortunate chance that the next moment will bring a change, and pursues this as far as his courage and his judgment can agree. We shall have something more to say on this subject, but before that we must show what are the signs of the scales turning.

The result of the whole combat consists in the sum total of the results of all partial combats; but these results of separate combats are settled by different considerations.

First by the pure moral power in the mind of the leading officers. If a General of Division has seen his battalions forced to succumb, it will have an influence on his demeanour and his reports, and these again will have an influence on the measures of the Commander-in-Chief; therefore even those unsuccessful partial combats which to all appearance are retrieved, are not lost in their results, and the impressions from them sum themselves up in the mind of the Commander without much trouble, and even against his will.

Secondly, by the quicker melting away of our troops, which can be easily estimated in the slow and relatively [Relatively, that is say to the shock of former days] little tumultuary course of our battles.

Thirdly, by lost ground.

All these things serve for the eye of the General as a compass to tell the course of the battle in which he is embarked. If whole batteries have been lost and none of the enemy’s taken; if battalions have been overthrown by the enemy’s cavalry, whilst those of the enemy everywhere present impenetrable masses; if the line of fire from his order of battle wavers involuntarily from one point to another; if fruitless efforts have been made to gain certain points, and the assaulting battalions each, time been scattered by well-directed volleys of grape and case;--if our artillery begins to reply feebly to that of the enemy--if the battalions under fire diminish unusually, fast, because with the wounded crowds of unwounded men go to the rear;--if single Divisions have been cut off and made prisoners through the disruption of the plan of the battle;--if the line of retreat begins to be endangered: the Commander may tell very well in which direction he is going with his battle. The longer this direction continues, the more decided it becomes, so much the more difficult will be the turning, so much the nearer the moment when he must give up the battle. We shall now make some observations on this moment.

We have already said more than once that the final decision is ruled mostly by the relative number of the fresh reserves remaining at the last; that Commander who sees his adversary is decidedly superior to him in this respect makes up his mind to retreat. It is the characteristic of modern battles that all mischances and losses which take place in the course of the same can be retrieved by fresh forces, because the arrangement of the modern order of battle, and the way in which troops are brought into action, allow of their use almost generally, and in each position. So long, therefore, as that Commander against whom the issue seems to declare itself still retains a superiority in reserve force, he will not give up the day. But from the moment that his reserves begin to become weaker than his enemy’s, the decision may be regarded as settled, and what he now does depends partly on special circumstances, partly on the degree of courage and perseverance which he personally possesses, and which may degenerate into foolish obstinacy. How a Commander can attain to the power of estimating correctly the still remaining reserves on both sides is an affair of skilful practical genius, which does not in any way belong to this place; we keep ourselves to the result as it forms itself in his mind. But this conclusion is still not the moment of decision properly, for a motive which only arises gradually does not answer to that, but is only a general motive towards resolution, and the resolution itself requires still some special immediate causes. Of these there are two chief ones which constantly recur, that is, the danger of retreat, and the arrival of night.

If the retreat with every new step which the battle takes in its course becomes constantly in greater danger, and if the reserves are so much diminished that they are no longer adequate to get breathing room, then there is nothing left but to submit to fate, and by a well-conducted retreat to save what, by a longer delay ending in flight and disaster, would be lost.

But night as a rule puts an end to all battles, because a night combat holds out no hope of advantage except under particular circumstances; and as night is better suited for a retreat than the day, so, therefore, the Commander who must look at the retreat as a thing inevitable, or as most probable, will prefer to make use of the night for his purpose.

That there are, besides the above two usual and chief causes, yet many others also, which are less or more individual and not to be overlooked, is a matter of course; for the more a battle tends towards a complete upset of equilibrium the more sensible is the influence of each partial result in hastening the turn. Thus the loss of a battery, a successful charge of a couple of regiments of cavalry, may call into life the resolution to retreat already ripening.

As a conclusion to this subject, we must dwell for a moment on the point at which the courage of the Commander engages in a sort of conflict with his reason.

If, on the one hand the overbearing pride of a victorious conqueror, if the inflexible will of a naturally obstinate spirit, if the strenuous resistance of noble feelings will not yield the battlefield, where they must leave their honour, yet on the other hand, reason counsels not to give up everything, not to risk the last upon the game, but to retain as much over as is necessary for an orderly retreat. However highly we must esteem courage and firmness in War, and however little prospect there is of victory to him who cannot resolve to seek it by the exertion of all his power, still there is a point beyond which perseverance can only be termed desperate folly, and therefore can meet with no approbation from any critic. In the most celebrated of all battles, that of Belle-Alliance, Buonaparte used his last reserve in an effort to retrieve a battle which was past being retrieved. He spent his last farthing, and then, as a beggar, abandoned both the battle-field and his crown.