The difference is that when someone depicts Bush as a monkey, it's because they think he is foolish and are making fun of him. We assume The New Yorker doesn't think Obama is a terrorist, so why are they putting a big cartoon on their cover that makes him look like a terrorist? Because they are making fun of those who think he is one? A bit too subtle for the cover if you ask me. I have no problem with freedom of expression and The New Yorker can put whatever the hell they want on their cover, I just think they are getting the opposite message across from what they intended.