I suspect that the Muslim hijackers, in a strange way, thought they were maximizing human happiness by removing Americans from the world.
I haven't done any studies, but I have a feeling that people attend to authority when it supports their natural biases, and ignore authority when it opposes their natural biases.
This post needs to be air-dropped over the world's ten largest metropolitan areas. Actually, Harry Potter and the Methods of Rationality needs to be air-dropped, with translations where necessary, because it contains the same truths but is more entertaining. I think the same arguements apply to labeling your enemies as insane mutants, which is a somewhat gentler, more politically correct way of demonizing them. We tend to assume that the enemy is insane because we could not imagine doing such a thing, and are therefore Surprised by Reality. It might make sense to update our idea of "sanity."
Most religions believe that the escape option is reversible - otherwise there wouldn't be much point.