War is the province of chance. In no sphere of human activity is such a margin to be left for this intruder. It increases the uncertainty of every circumstance, and deranges the course of events.
Carl von ClausewitzIf we do not learn to regard a war, and the separate campaigns of which it is composed, as a chain of linked engagements each leading to the next, but instead succumb to the idea that the capture of certain geographical points or the seizure of undefended provinces are of value in themselves, we are liable to regard them as windfall profits.
Carl von Clausewitz