By the classification in question Clausewitz distinguished wars into those with a "Limited" object and those whose object was "Unlimited." Such a classification was entirely characteristic of him, for it rested not alone upon the material nature of the object, but on certain moral considerations to which he was the first to attach their real value in war. Other
writers such as Jomini had attempted to classify wars by the special purpose for which they were fought, but Clausewitz's long course of study convinced him that such a distinction was unphilosophical and bore no just relation to any tenable theory of war. Whether, that is, a war was positive or negative mattered much, but its special purpose, whether, for instance, according to Jomini's system, it was a war "to assert rights" or "to assist an ally" or "to acquire territory," mattered not at all.
Whatever the object, the vital and paramount question was the intensity with which the spirit of the nation was absorbed in its attainment. The real point to determine in approaching any war plan was what did the object mean to the two belligerents, what sacrifices would they make for it, what risks were they prepared to run? It was thus he stated his view. "The smaller the sacrifice we demand from our opponent, the smaller presumably will be the means of resistance he will employ, and the smaller his means, the smaller will ours be required to be. Similarly the smaller our political object, the less value shall we set upon it and the more easily we shall be induced to abandon it." Thus the political object of the war, its original motive, will not only determine for both belligerents reciprocally the aim of the force they use, but it will also be the standard of the intensity of the efforts they will make. So he concludes there may be wars of all degrees of importance and energy from a war of extermination down to the use of an army of observation. So also in the naval sphere there may be a life and death struggle for maritime supremacy or hostilities which never rise beyond a blockade.
Such a view of the subject was of course a wide departure from the theory of "Absolute War" on which Clausewitz had started working. Under that theory "Absolute War" was the
ideal form to which all war ought to attain, and those which fell short of it were imperfect wars cramped by a lack of true military spirit. But so soon as he had seized the fact that in actual life the moral factor always must override the purely military factor, he saw that he had been working on too narrow a basis—a basis that was purely theoretical in that it ignored the human factor. He began to perceive that it was logically unsound to assume as the foundation of a strategical system that there was one pattern to which all wars ought to conform. In the light of his full and final apprehension of the value of the human factor he saw wars falling into two well-marked categories, each of which would legitimately be approached in a radically different manner, and not necessarily on the lines of "Absolute War."
He saw that there was one class of war where the political object was of so vital an importance to both belligerents that they would tend to fight to the utmost limit of their endurance to secure it. But there was another class where the object was of less importance, that is to say, where its value to one or both the belligerents was not so great as to be worth unlimited sacrifices of blood and treasure. It was these two kinds of war he designated provisionally "Unlimited" and "Limited," by which he meant not that you were not to exert the force employed with all the vigour you could develop, but that there might be a limit beyond which it would be bad policy to spend that vigour, a point at which, long before your force was exhausted or even fully developed, it would be wiser to abandon your object rather than to spend more upon it.
This distinction it is very necessary to grasp quite clearly, for it is often superficially confused with the distinction already referred to, which Clausewitz drew in the earlier part of his work—that is, the distinction between what he called the character of modern war and the character of the wars which preceded the Napoleonic era. It will be remembered he
insisted that the wars of his own time had been wars between armed nations with a tendency to throw the whole weight of the nation into the fighting line, whereas in the seventeenth and eighteenth centuries wars were waged by standing armies and not by the whole nation in arms. The distinction of course is real and of far-reaching consequences, but it has no relation to the distinction between "Limited" and "Unlimited" war. War may be waged on the Napoleonic system either for a limited or an unlimited object.
A modern instance will serve to clear the field. The recent Russo-Japanese War was fought for a limited object—the assertion of certain claims over territory which formed no part of the possessions of either belligerent. Hostilities were conducted on entirely modern lines by two armed nations and not by standing armies alone. But in the case of one belligerent her interest in the object was so limited as to cause her to abandon it long before her whole force as an armed nation was exhausted or even put forth. The expense of life and treasure which the struggle was involving was beyond what the object was worth.
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