A lot of people are very angry at the government right now. VERY angry. In no way are this man's actions justified, but it shows just how angry & frustrated people are getting.
Personally, I'm of the opinion that offing yourself in some stupid prank is easy, but working hard to make real change in a cause you believe in, now THAT'S hard. It's so hard most people would rather sit around & complain than actually take any actions towards it. Some people take some action, like writing their representatives or something, and get discouraged quickly when nothing happens, then they feel like they can't make a difference no matter what. Instead of persevering & working some end up going off the deep end and doing something incredibly stupid (like flying their plane into a building) because they feel like they have no other recourse.