My favorite philosopher, John Stuart Mill:
"War is an ugly thing, but not the ugliest of things. The decayed and degraded state of moral and patriotic feeling which thinks that nothing is worth war is much worse. The person who has nothing for which he is willing to fight, nothing which is more important than his own personal safety, is a miserable creature and has no chance of being free unless made and kept so by the exertions of better men than himself."
Heinlein:
"Anyone who clings to the historically untrue—and thoroughly immoral—doctrine that "violence never settles anything" I would advise to conjure the ghosts of Napoleon Bonaparte and the Duke of Wellington and let them debate it. The ghost of Hitler could referee, and the jury might well be the Dodo, the Great Auk and the Passenger Pigeon. Violence, naked force, has settled more issues in history than has any other factor, and the contrary opinion is wishful thinking at its worst. Breeds that forget this basic truth have always paid for it with their lives and freedom."
And of course, the anonymous:
"Payback is a bitch."
