The Relations of the Offensive and Defensive to each other in Strategy

Let us ask again, first of all, what are the circumstances which ensure a successful result in strategy?

In strategy there is no victory, as we have before said. On the one hand, the strategic success is the successful preparation of the tactical victory; the greater this strategic success, the more probable becomes the victory in the battle. On the other hand, strategic success lies in the making use of the victory gained. The more events the strategic combinations can in the sequel include in the consequences of a battle gained, the more strategy can lay hands on amongst the wreck of all that has been shaken to the foundation by the battle, the more it sweeps up in great masses what of necessity has been gained with great labour by many single hands in the battle, the grander will be its success. Those things which chiefly lead to this success, or at least facilitate it, consequently the leading principles of efficient action in strategy, are as follow:

1 The advantage of ground.

2 The surprise, let it be either in the form of an actual attack by surprise or by the unexpected display of large forces at certain points.

3 The attack from several quarters (all three, as in tactics).

4 The assistance of the theatre of war by fortresses, and everything belonging to them.

5 The support of the people.

6 The utilisation of great moral forces.

Now, what are the relations of offensive and defensive with respect to these things?

The defender has the advantage of ground; the assailant that of the attack by surprise in strategy, as in tactics. But respecting the surprise, we must observe that it is infinitely more efficacious and important in the former than in the latter. In tactics, a surprise seldom rises to the level of a great victory, while in strategy it often finishes the war at one stroke. But at the same time we must observe that the advantageous use of this means supposes some great and uncommon, as well as decisive error committed by the adversary, therefore it does not alter the balance much in favour of the offensive.
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Now it confessedly lies in the nature of things, that on account of the greater spaces in strategy, the enveloping attack, or the attack from several sides, as a rule is only possible for the side which has the initiative, that is the offensive, and that the defensive is not in a condition, as he is in tactics, in the course of the action, to turn the tables on the enemy by surrounding him, because he has it not in his power either to draw up his forces with the necessary depth relatively, or to conceal them sufficiently: but then, of what use is the facility of enveloping to the offensive, if its advantages are not forthcoming?
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The fourth principle, the assistance of the theatre of war, is naturally an advantage on the side of the defensive. If the attacking army opens the campaign, it breaks away from its own theatre, and is thus weakened, that is, it leaves fortresses and depots of all kinds behind it. The greater the sphere of operations which must be traversed, the more it will be weakened (by marches and garrisons); the army on the defensive continues to keep up its connection with everything, that is, it enjoys the support of its fortresses, is not weakened in any way, and is near to its sources of supply.

The support of the population as a fifth principle is not realised in every defence, for a defensive campaign may be carried on in the enemy’s country, but still this principle is only derived from the idea of the defensive, and applies to it in the majority of cases. Besides by this is meant chiefly, although not exclusively, the effect of calling out the last reserves, and even of a national armament, the result of which is that all friction is diminished, and that all resources are sooner forthcoming and flow in more abundantly.
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