How about the Japanese actually wore uniforms? How about the Japanese collectively surrendered. How about Al Queda doesn't, and won't.
That is, of course, also true. Hanks fails on every level in his argument.
No, dummy. We annihilated them because A) they warred on us first, and B) they insisted upon it.
The marines learned very early, at the battle of Alligator Creek on Guadalcanal, that treating Japanese soldiers by the rules of war very often had fatal consequences.