"Why were they laughing at Bush's answer? I don't understand what was so funny."
Exactly. It was a question by some smart-ass college-kid to get attention and to embarrass the President. The 'joke' was that he got the President to take him seriously. This, to some, is funny.
I was proud of the President for refusing to this fool's level. He's been suffering the abuse of fools for a long time now. And he won this one.