That the defensive in an especial manner enjoys the assistance which ground affords is plain in itself; as to what concerns the advantage which the defensive has in surprising by the force and form of his attacks, that results from the offensive being obliged to approach by roads and paths where he may be easily observed, whilst the defensive conceals his position, and, until almost the decisive moment, remains invisible to his opponent.—Since the true method of defence has been adopted, reconnaissances have gone quite out of fashion, that is to say, they have become impossible. Certainly reconnaissances are still made at times, but they seldom bring home much with them. Immense as is the advantage of being able to examine well a position, and become perfectly acquainted with it before a battle, plain as it is that he (the defensive) who lies in wait near such a chosen position can much more easily effect a surprise than his adversary, yet still to this very hour the old notion is not exploded that a battle which is accepted is half lost. This comes from the old kind of defensive practised twenty years ago, and partly also in the Seven Years’ War, when the only assistance expected from the ground was that it should be difficult of approach in front (by steep mountain slopes, etc., etc.), when the little depth of the positions and the difficulty of moving the flanks produced such weakness that the armies dodged one another from one hill to another, which increased the evil. If some kind of support were found on which to rest the wings, then all depended on preventing the army stretched along between these points, like a piece of work on an embroidery frame, from being broken through at any point. The ground occupied possessed a direct value at every point, and therefore a direct defence was required everywhere. Under such circumstances, the idea of making a movement or attempting a surprise during the battle could not be entertained; it was the exact reverse of what constitutes a good defence, and of that which the defence has actually become in modern warfare.
In reality, contempt for the defensive has always been the result of some particular method of defence having become worn out (outlived its period); and this was just the case with the method we have now mentioned, for in times antecedent to the period we refer to, that very method was superior to the offensive.
If we go through the progressive development of the modern art of war, we find that at the commencement—that is the Thirty Years’ War and the war of the Spanish Succession—the deployment and drawing up of the army in array, was one of the great leading points connected with the battle. It was the most important part of the plan of the battle. This gave the defensive, as a rule, a great advantage, as he was already drawn up and deployed. As soon as the troops acquired greater capability of manœuvring, this advantage ceased, and the superiority passed over to the side of the offensive for a time. Then the defensive sought shelter behind rivers or deep valleys, or on high land. The defensive thus recovered the advantage, and continued to maintain it until the offensive acquired such increased mobility and expertness in manœuvring that he himself could venture into broken ground and attack in separate columns, and therefore became able to turn his adversary. This led to a gradual increase in the length of positions, in consequence of which, no doubt, it occurred to the offensive to concentrate at a few points, and break through the enemy’s thin line. The offensive thus, for a third time, gained the ascendancy, and the defence was again obliged to alter its system. This it has done in recent wars by keeping its forces concentrated in large masses, the greater part not deployed, and, where possible, concealed, thus merely taking up a position in readiness to act according to the measures of the enemy as soon as they are sufficiently revealed.
This does not preclude a partially passive defence of the ground; its advantage is too great for it not to be used a hundred times in a campaign. But that kind of passive defence of the ground is usually no longer the principal affair: that is what we have to do with here.
If the offensive should discover some new and powerful element which it can bring to its assistance—an event not very probable, seeing the point of simplicity and natural order to which all is now brought—then the defence must again alter its method. But the defensive is always certain of the assistance of ground, which insures to it in general its natural superiority, as the special properties of country and ground exercise a greater influence than ever on actual warfare.
CHAPTER III.
The Relations of the Offensive and Defensive to Each Other in Strategy
Let us ask again, first of all, what are the circumstances which insure 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.