Decreasing Force of the Attack

This is one of the principal points in strategy: on its right valuation in the concrete, depends our being able to judge correctly what we are able to do.

The decrease of absolute power arises through:

1 The object of the attack, the occupation of the enemy’s country; this generally commences first after the first decision, but the attack does not cease upon the first decision.

2 The necessity imposed on the attacking army to guard the country in its rear, in order to preserve its line of communication and means of subsistence.

3 Losses in action, and sickness.

4 Distance of the various depots of supplies and reinforcements.

5 Sieges and blockades of fortresses.

6 Relaxation of efforts.

7 Secession of allies.

But frequently, in opposition to these weakening causes, there may be many others which contribute to strengthen the attack. It is clear, at all events, that a net result can only be obtained by comparing these different quantities; thus, for example, the weakening of the attack may be partly or completely compensated, or even surpassed by the weakening of the defensive. This last is a case which rarely happens.
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