Preparation for war, rightly understood, A falls under two heads,—preparation and preparedness. The one is a question mainly of material, and is constant in its action. The second involves an idea of completeness. When, at a particular moment, preparations are completed, one is prepared—not otherwise. There may have been made a great deal of very necessary preparation for war without being prepared. Every constituent of preparation may be behindhand, or some elements may be perfectly ready, while others are not. In neither case can a state be said to be prepared. In the matter of preparation for war, one clear idea should be absorbed first by every one who, recognizing that war is still a possibility, desires to see his country ready. This idea is that, however defensive in origin or in political character a war may be, the assumption of a simple defensive in war is ruin. War, once declared, must be waged offensively, aggressively. The enemy must not be fended off, but smitten down. You may then spare him every exaction, relinquish every gain; but till down he must be struck incessantly and remorselessly. Preparation, like most other things, is a question both of kind and of degree, of quality and of quantity. As regards degree, the general lines upon which it is determined have been indicated broadly in the preceding part of this article. The measure of degree is the estimated force which the strongest probable enemy can bring against you, allowance being made for clear drawbacks upon his total force, imposed by his own embarrassments and responsibilities in other parts of the world. The calculation is partly military, partly political, the latter, however, being the dominant factor in the premises. In kind, preparation is twofold,—defensive and offensive. The former exists chiefly for the sake of the latter, in order that offense, the determining factor in war, may put forth its full power, unhampered by concern for the protection of the national interests or for its own resources. In naval war, coast defense is the defensive factor, the navy the offensive. Coast defense, when adequate, assures the naval commander-in-chief that his base of operations—the dockyards and coal depots—is secure. It also relieves him and his government, by the protection afforded to the chief commercial centers, from the necessity of considering them, and so leaves the offensive arm perfectly free.