On War

by Carl von Clausewitz

A defence of the country, therefore, only waits for attack on the country; a defence of a theatre of war an attack on the theatre of war; and the defence of a position the attack of that position. Every positive, and consequently more or less offensive, kind of action which the defensive uses after the above period of waiting for, does not negative the idea of the continuance of the defensive; for the state of expectation, which is the chief sign of the same, and its chief advantage, has been realised.

The conception of war, campaign, and battle, in relation to time, are coupled respectively with the ideas of country, theatre of war, and position, and on that account they have the same relations to the present subject.

The defensive consists, therefore, of two heterogeneous parts, the state of expectancy and that of action. By having referred the first to a definite subject, and therefore given it precedence of action, we have made it possible to connect the two into one whole. But an act of the defensive, especially a considerable one, such as a campaign or a whole war, does not, as regards time, consist of two great halves, the first the state of mere expectation, the second entirely of a state of action; it is a state of alternation between the two, in which the state of expectation can be traced through the whole act of the defensive like a continuous thread.

We give to this state of expectation so much importance simply because it is demanded by the nature of the thing. In preceding theories of war it has certainly never been brought forward as an independent conception, but in reality it has always served as a guide, although often unobserved. It is such a fundamental part of the whole act of war, that the one without the other appears almost impossible; and we shall therefore often have occasion to recur to it hereafter by calling attention to its effects in the dynamic action of the powers called into play.

For the present we shall employ ourselves in explaining how the principle of the state of expectation runs through the act of defence, and what are the successive stages in the defence itself which have their origin in this state.

In order to establish our ideas on subjects of a more simple kind, we shall defer the defence of a country, a subject on which a very great diversity of political influences exercises a powerful effect, until we come to the Book on the Plan of War; and as on the other hand, the defensive act in a position or in a battle is matter of tactics, which only forms a starting point for strategic action as a whole, we shall take the defence of a theatre, of war as being the subject, in which we can best show the relations of the defensive.

We have said, that the state of expectation and of action—which last is always a counterstroke, therefore a reaction—are both essential parts of the defensive; for without the first, there would be no defensive, without the second no war. This view led us before to the idea of the defensive being nothing but the stronger form of war, in order the more certainly to conquer the enemy; this idea we must adhere to throughout, partly because it alone saves us in the end from absurdity, partly, because the more vividly it is impressed on the mind, so much the greater is the energy it imparts to the whole act of the defensive.

If therefore we should make a distinction between the reaction, constituting the second element of the defensive, and the other element which consists in reality in the repulse only of the enemy;—if we should look at expulsion from the country, from the theatre of war, in such a light as to see in it alone the necessary thing by itself, the ultimate object beyond the attainment of which our efforts should not be carried, and on the other hand, regard the possibility of a reaction carried still further, and passing into the real strategic attack, as a subject foreign to and of no consequence to the defence,—such a view would be in opposition to the nature of the idea above represented, and therefore we cannot look upon this distinction as really existing, and we must adhere to our assertion, that the idea of revenge must always be at the bottom of every defensive; for otherwise, however much damage might be occasioned to the enemy, by a successful issue of the first reaction, there would always be a deficiency in the necessary balance of the dynamic relations of the attack and defence.

We say, then, the defensive is the more powerful form of making war, in order to overcome the enemy more easily, and we leave to circumstances to determine whether this victory over the object against which the defence was commenced is sufficient or not.

But as the defensive is inseparable from the idea of the state of expectation, that object, the defeat of the enemy, only exists conditionally, that is, only if the offensive takes place; and otherwise (that is, if the offensive stroke does not follow) of course the defensive is contented with the maintenance of its possessions; this maintenance is therefore its object in the state of expectation, that is, its immediate object; and it is only as long as it contents itself with this more modest end, that it preserves the advantages of the stronger form of war.