This second distinction—­that is, between Limited and Unlimited wars—­Clausewitz regarded as of greater importance than his previous one founded on the negative or positive nature of the object.  He was long in reaching it.  His great work On War as he left it proceeds almost entirely on the conception of offensive or defensive as applied to the Napoleonic ideal of absolute war.  The new idea came to him towards the end in the full maturity of his prolonged study, and it came to him in endeavouring to apply his strategical speculations to the practical process of framing a war plan in anticipation of a threatened breach with France.  It was only in his final section On War Plans that he began to deal with it.  By that time he had grasped the first practical result to which his theory led.  He saw that the distinction between Limited and Unlimited war connoted a cardinal distinction in the methods of waging it.  When the object was unlimited, and would consequently call forth your enemy’s whole war power, it was evident that no firm decision of the struggle could be reached till his war power was entirely crushed.  Unless you had a reasonable hope of being able to do this it was bad policy to seek your end by force—­that is, you ought not to go to war.  In the case of a limited object, however, the complete destruction of the enemy’s armed force was beyond what was necessary.  Clearly you could achieve your end if you could seize the object, and by availing yourself of the elements of strength inherent in the defensive could set up such a situation that it would cost the enemy more to turn you out than the object was worth to him.

Here then was a wide difference in the fundamental postulate of your war plan.  In the case of an unlimited war your main strategical offensive must be directed against the armed forces of the enemy; in the case of a limited war, even where its object was positive, it need not be.  If conditions were favourable, it would suffice to make the object itself the objective of your main strategical offensive.  Clearly, then, he had reached a theoretical distinction which modified his whole conception of strategy.  No longer is there logically but one kind of war, the Absolute, and no longer is there but one legitimate objective, the enemy’s armed forces.  Being sound theory, it of course had an immediate practical value, for obviously it was a distinction from which the actual work of framing a war plan must take its departure.

A curious corroboration of the soundness of these views is that Jomini reached an almost identical standpoint independently and by an entirely different road.  His method was severely concrete, based on the comparison of observed facts, but it brought him as surely as the abstract method of his rival to the conclusion that there were two distinct classes of object.  “They are of two different kinds,” he says, “one which may be called territorial or geographical ... the other on the contrary consists exclusively