It is true these errors first displayed themselves in the war, and the events of the war completely disappointed the expectations which policy entertained. But this did not take place because policy neglected to consult its military advisers. That art of war in which the politician of the day could believe, namely, that derived from the reality of war at that time, that which belonged to the policy of the day, that familiar instrument which policy had hitherto used -- that art of war, I say, was naturally involved in the error of policy, and therefore could not teach it anything better. It is true that war itself underwent important alterations both in its nature and forms, which brought it nearer to its absolute form; but these changes were not brought about because the French government had, to a certain extent, delivered itself from the leading-strings of policy; they arose from an altered policy, produced by the French Revolution, not only in France, but over the rest of Europe as well. This policy had called forth other means and other powers, by which it became possible to conduct war with a degree of energy which could not have been thought of otherwise.

Therefore, the actual changes in the art of war are a consequence of alterations in policy; and, so far from being an argument for the possible separation of the two, they are, on the contrary, very strong evidence of the intimacy of their connection.

Therefore, once more: war is an instrument of policy; it must necessarily bear its character, it must measure with its scale: the conduct of war, in its great features, is therefore policy itself, which takes up the sword in place of the pen, but does not on that account cease to think according to its own laws.
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