I was never wild about Hitchens when he was "on message" (though he's always been a highly entertaining writer), but I think he has a point when he emphasises how nasty a regime Iraq is. Just because the US is going to invade Iraq (my bet is early November. Any others?), doesn't mean that the left should cosy up to Saddam a la George Galloway. You don't have to look hard for revolting human rights crimes by Saddam, and while he probably hasn't been able to get nuclear materials, that hasn't been for lack of trying. Yes Israel has nuclear weapons, but that's hardly an argument for allowing Saddam to get them.
I doubt very much that the left can do anything to stop this invasion, but perhaps they can prevent Saddam being replaced by another dictator and the Kurds being screwed again. There is a depressing tendency, which Hitchens has rightly pointed out, to think in binary terms on these issues. That many of the left defended Milosovich blew much of the credibility that the left had built up. Why destroy the remainder?