Depends on who we're talking about. Richard Reid? Insane. Osama? Not insane.
I don't know how insane this guy was (or how sane Osama was), but he sure does bear a more striking resemblance to your garden variety Islamic terrorist than people seem willing to admit. Different ideology, but he reeks of the same level of fanaticism.
I've spent a lot of time this week learning about Muslim tradition when it comes to death and burial, and I'm even more amazed by the number of rules involved in the Muslim faith and the sheer obedience it requires. The discipline is used in the Muslims I know to live a life of added peace and devotion to their families, but we have seen how easily that gets twisted. There's a part of the brain wired for faith, and when your faith requires obedience, it's dangerous if you get it turned the wrong way.
This guy seems to have done this out of intense fear and some sense of necessity to protect his community. My fear is that this whole persecuted Christian routine (and Lindsey Graham trotted it right out) is going to lead to an increase in "justifiable" violence from the right.