Retreat into the Interior of the Country

We have considered the voluntary retreat into the heart of the country as a particular indirect form of defence through which it is expected the enemy will be destroyed, not so much by the sword as by exhaustion from his own efforts. In this case, therefore, a great battle is either not supposed, or it is assumed to take place when the enemy’s forces are considerably reduced.

Every assailant in advancing diminishes his military strength by the advance.
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This loss in the advance is increased if the enemy has not been beaten, but withdraws of his own accord with his forces intact, and offering a steady continuous resistance, sells every step of ground at a bloody price, so that the advance is a continuous combat for ground and not a mere pursuit.

On the other hand, the losses which a party on the defensive suffers on a retreat, are much greater if his retreat has been preceded by a defeat in battle than if his retreat is voluntary.
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A regularly measured daily resistance, that is, one which each time only lasts as long as the balance of success in the combat can be kept wavering, and in which we secure ourselves from defeat by giving up the ground which has been contested at the right moment, will cost the assailant at least as many men as the defender in these combats, for the loss which the latter by retiring now and again must unavoidably suffer in prisoners, will be balanced by the losses of the other under fire, as the assailant must always fight against the advantages of the ground.
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The result will be that the two armies will wear each other away in nearly equal proportions in these perpetual collisions.

It is quite different in the pursuit of a beaten army. Here the troops lost in battle, the general disorganisation, the broken courage, the anxiety about the retreat, make such a resistance on the part of the retreating army very difficult, in many cases impossible; and the pursuer who, in the former case, advances extremely cautiously, even hesitatingly, like a blind man, always groping about, presses forward in the latter case with the firm tread of the conqueror, with the overweening spirit which good fortune imparts, with the confidence of a demi-god, and the more daringly he urges the pursuit so much the more he hastens on things in the direction which they have already taken, because here is the true field for the moral forces which intensify and multiply themselves without being restricted to the rigid numbers and measures of the physical world.
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The army in retreat has the means of collecting provisions everywhere, and he marches towards them, whilst the pursuer must have everything brought after him which, as long as he is in motion, even with the shortest lines of communication, is difficult, and on that account begets scarcity from the very first

All that the country yields will be taken for the benefit of the retreating army first, and will be mostly consumed. Nothing remains but wasted villages and towns, fields from which the crops have been gathered, or which are trampled down, empty wells, and muddy brooks.

The pursuing army, therefore, from the very first day has frequently to contend with the most pressing wants. On taking the enemy’s supplies he cannot reckon; it is only through accident, or some unpardonable blunder on the part of the enemy, that here and there some little falls into his hands.

Thus there can be no doubt that in countries of vast dimensions, and when there is no extraordinary disproportion between the belligerent powers, a relation may be produced in this way between the military forces, which holds out to the defensive an immeasurably greater chance of a final result in his favour than he would have had if there had been a great battle on the frontier. Not only does the probability of gaining a victory become greater though this alteration in the proportions of the contending armies, but the prospects of great results from the victory are increased as well, through the change of position. What a difference between a battle lost close to the frontier of our country and one in the middle of the enemy’s country! Indeed, the situation of the assailant is often such at the end of his first start, that