Very few people, sane or otherwise, can pull the trigger on assured destruction knowing they cannot win. It takes a true fanatic, not merely a despot. I have no doubt that a Bin Laden or someone like him would not hesitate in blowing up everything including themselves even if they could not win. Saddam is a different sort of problem. Alive, he remains in the game. He enjoys power too much to willingly take his own life, I think. Alive, he's got a chance to come back and be a player. It happened during the First Gulf War, right? So maybe he figures that he can eventually outlast the US, but only if he is alive.
Then there is also the question of whether he knew he didn't have the goodies. If Saddam called me into a room and asked me if I was meeting production goals, my response would be an immediate "yes" and I'd provide all sorts of documentation, despite the fact I had produced nothing and made it all up. I read where lying to Saddam to keep from getting killed was common by Iraqi scientists, especially those in the Iraqi defense and research sectors. The embargo was keeping them from getting what they needed to make these weapons but they didn't dare tell Saddam that. So they lied. Saddam might have thought he had the weapons when in fact, he had nothing.
