There's probably no real reason, the guy is likely just a lunatic. Happens more frequently in America.
that's usually the reason in the U.S., but this is said to be politically motivated. so, a politically motivated lunatic.
and of course it happens more frequently in America. Not sure if you mean it this way, but I always see this comment as some kind of justification when something bad happens in another country. America is kind of fucking enormous and the odds for this kind of thing are up exponentially over any Euro or Asian country (China, India, Russia, etc. notwithstanding, obviously.)
smh @ terrorist comments. the bomb was their style but not sending in one dude to shoot up a camp...they'd have an organized firing squad, if they were to even do that kind of thing. They'd probably just bomb the camp too.