The U.S. government has at times messed up. It has done some bad things. It has made mistakes. It has donemisguided or expedient things. In the case of one recent President it did some things that would clearly qualify as war-crimes if done by others. None of this has anything to do with Osama bin Ladin and his cult. He is angry because we are, and further angry because we set foot on the "sacred soil" of Saudi Arabia. It did not matter why we did so - only that we did.
It also would not matter even if we did indeed deserve it - the attack simply cannot be permitted to stand.
There will always be evil. God knows us, that is why he instituted civil government to punish lawbreakers to protect those who keep the law.