Well, this is a rather different issue, isn't it? Personally, I think ethical treatment of others, in war or not, is an imperative for all cultures. I am simply a part of this one, so I speak my piece for what I see as the betterment of our culture/society.
Ultimately, should our standards of conduct be the same as terrorists? Or the evil regimes we fight and claim to be (and, in fact, obviously are) better than? It shouldn't matter what Hussein's Iraq does, or what Al Qaeda does. We should have our own standard of ethics and want to be held to a higher standard, because we aim to be much, much, much better than tyrannies and terrorists. And we should be disappointed whenever we fail to meet our own standards, rather than take solace in the fact that the people we fight do bad things.