Like Ponrauil said, one can be anti-communist and anti-war or anti-aggression. At the same time, people can be stupid enough to believe in the basic tenets of communism and still think war is wrong except when it advances the collectivist doctorine. It all comes down to whether or not they hold to a consistent set of principles. I still think you should have him read Hayek's Road To Serfdom.

Adrian