"War, Nobby. Huh! What is it good for?" he said.
"Dunno, sarge. Freeing slaves, maybe?"
"Absol--Well, okay."
"Defending yourself from a totalitarian aggressor?"
"All right, I'll grant you that, but--"
"Saving civilization against a horde of--"
"It doesn't do any good in the long run is what I'm saying, Nobby, if you'd listen for five seconds together," said Fred Colon sharply.
"Yeah, but in the long run what does, sarge?"

-- Terry Pratchett, Thud!