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 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.
- Through 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.
- Through losses in action and through sickness.
- Distance of the various depôts of supplies and reinforcements.
- Sieges and blockades of fortresses.
- Relaxation of efforts.
- 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