Unity of thought is only to be obtained by "the conception that war is only a part of political intercourse, therefore by no means an independent thing in itself." "And how can we conceive it to be otherwise? Does the cessation of diplomatic notes stop the political relations between different nations and governments? Is not war merely another kind of writing and language for political thoughts?" "Accordingly war can never be separated from political intercourse; and if, in the consideration of the matter, this is done in any way, all the threads of the different relations are, to a certain extent, broken, and we have before us a senseless thing without an object."
"If war belongs to policy, it will naturally take its character from policy. If the policy is grand and powerful, so will also be the war, and this may be carried to the point at which war attains to its absolute form." "Only through this kind of view war recovers unity; only by it can we see all wars of one kind, and it is only through it that the judgment can obtain the true and perfect basis and point of view from which great plans may be traced out and determined upon."
"There is upon the whole nothing more important in life than to find out the right point of view from which things should be looked at and judged of, and then to keep to that point; for we can only apprehend the mass of events in their unity from one standpoint; and it is only the keeping to one point of view that guards us from inconsistency." "We can only look at policy here as the representative of the interests generally of the whole community," and "wars are in reality only the expressions or manifestations of policy itself."
To the student of history this unity of conception is equally necessary, for it supplies the key to many a military puzzle. Without it we can never understand, for instance, Napoleon's conduct in 1812, 1813, 1814; nor without it can we see the compelling reason of many battles, apparently fought against military judgment, such, for instance, as Borodino, Leipzig, Sedan, etc. We have to remember that these and many other battles, as, for instance, Ladysmith, were fought from a political, not a military, motive. It is a well-known fact that the strategist frequently has to alter and adapt his plans so as to suit overmastering political necessity. Yet many people have failed to draw therefrom the generalization of Clausewitz that "war is only a continuation of State policy by other means." But having got it now, let us hold fast to it, with all its consequences.
Some Knowledge of War necessary for Statesmen
"From this point of view there is no longer in the nature of things a necessary conflict between the political and military interests, and where it appears it is therefore to be regarded as imperfect knowledge only. That policy makes demands upon the war which it cannot respond to, would be contrary to the supposition that it knows the instrument it is going to use, therefore contrary to a natural and indispensable supposition."
"None of the principal plans which are required for a war can be made without an insight into the political relations; and in reality when people speak, as they often do, of the prejudicial influence of policy on the conduct of a war, they say in reality something very different to what they intend. It is not this influence, but the policy itself which should be found fault with. If policy is right, if it succeeds in hitting the object, then it can only act on the war also with advantage; and if this influence of policy causes a divergence from the object, the cause is to be looked for in a mistaken policy.
"It is only when policy promises itself a wrong effect from certain military means and measures, an effect opposed to their nature, that it can exercise a prejudicial effect on war by the course it prescribes. Just as a person in a language with which he is not conversant sometimes says what he does not intend, so policy, when intending right, may often order things which do not tally with its own views.
"This has happened times without end, and it shows that a certain knowledge of the nature of war is essential to the management of political intercourse."