It's a bit like Dr. Frankenstein killing the monster, though, really. He was able to rise in power because of our actions in Iraq. I hope people remember this before they decide to like Bush again.
He needed to die, and an air strike was too good a way for someone who beheaded innocent people to go. I'd much rather he be a dead martyr than a live asshole killing people both directly, and by command.
Unfortunately, this, in my eyes, is the only way to deal with this threat. Keep killing them before they kill us. It's unfortunate, but if we try to negotiate with them, then their tactics have prevailed, and that will encourage them to do the same or worse the next time they don't get their way. This was brought down upon those people by their own actions though.
God, when I read this, it makes me sound like I am pro-war in Iraq. I am absolutely not, but this asshole had to go, as do all of his followers, and any like him.