I remember when I first started playing the Return to Castle Wolfenstein multiplayer demo. I had to pause before I started playing as an Axis soldier. What was I doing playing a Nazi?
I'm older than most gamers and my parents went through WWII. It wasn't ancient history to them and it wasn't to me either. My father was interned as a child by the Japanese. The war affected me profoundly in an identafiable way even though I was born more than two decades after the guns stopped firing. My father's temperment had been shaped by the screaming rages that the Japanese who guarded him had indulged in.
But the war was "ancient history" to most of the people I played with. They didn't personally identify with it at all it seemed. However I got over my initial qualms about playing the Germans. As other people noted, they seemed to have better weapons.
So I have sympathy for those who think this games in poor taste. I also don't want people glossing over the differences between the ideals of western civilization embodied in things like English common law and totalitarian versions of Islam espoused by the taliban(I'm somewhat sympathetic to arguments that that's the only kind).