Why Did We Attack Iraq?

Why did we do this? We didn't have enough evidence to attack (yeah, they had a lot of WMDs) and after awhile I think the war just turned into a hunt for Saddam (Krusty the Klown: Saddam Hussein? More like So Damn Insane!). Also hundreds of innocent people die every day over there and what for? Just so Dubya canhave some fun?