As one of these simplified characteristic points as a mental appliance, we look upon the principle of watching continually over the co-operation of all forces, or in other words, of keeping constantly in view that no part of them should ever be idle. Whoever has forces where the enemy does not give them sufficient employment, whoever has part of his forces on the march—that is, allows them to lie dead—while the enemy’s are fighting, he is a bad manager of his forces. In this sense there is a waste of forces, which is even worse than their employment to no purpose. If there must be action, then the first point is that all parts act, because the most purposeless activity still keeps employed and destroys a portion of the enemy’s force, whilst troops completely inactive are for the moment quite neutralised. Unmistakably this idea is bound up with the principles contained in the last three chapters, it is the same truth, but seen from a somewhat more comprehensive point of view and condensed into a single conception.
The length to which the geometrical element or form in the disposition of military force in War can become a predominant principle, we see in the art of fortification, where geometry looks after the great and the little. Also in tactics it plays a great part. It is the basis of elementary tactics, or of the theory of moving troops; but in field fortification, as well as in the theory of positions, and of their attack, its angles and lines rule like law givers who have to decide the contest. Many things here were at one time misapplied, and others were mere fribbles; still, however, in the tactics of the present day, in which in every combat the aim is to surround the enemy, the geometrical element has attained anew a great importance in a very simple, but constantly recurring application. Nevertheless, in tactics, where all is more movable, where the moral forces, individual traits, and chance are more influential than in a war of sieges, the geometrical element can never attain to the same degree of supremacy as in the latter. But less still is its influence in Strategy; certainly here, also, form in the disposition of troops, the shape of countries and states is of great importance; but the geometrical element is not decisive, as in fortification, and not nearly so important as in tactics.—The manner in which this influence exhibits itself, can only be shown by degrees at those places where it makes its appearance, and deserves notice. Here we wish more to direct attention to the difference which there is between tactics and Strategy in relation to it.
In tactics time and space quickly dwindle to their absolute minimum. If a body of troops is attacked in flank and rear by the enemy, it soon gets to a point where retreat no longer remains; such a position is very close to an absolute impossibility of continuing the fight; it must therefore extricate itself from it, or avoid getting into it. This gives to all combinations aiming at this from the first commencement a great efficiency, which chiefly consists in the disquietude which it causes the enemy as to consequences. This is why the geometrical disposition of the forces is such an important factor in the tactical product.