How badly would the US and the Allies would have behaved to make it happen? Don't dismiss it out of hand -- if the 1930's had gone only slightly differently (a world where Huey Long hadn't been assassinated, perhaps), we might have found ourselves fighting WITH Germany in WWII. We already had detention camps, and we were the GOOD guys.
Put aside the mental horror of such a world for the moment, and consider Saddam's death sentence. Some time in the next 30 days he will be publicly executed in Iraq, swung from the neck until dead. While the more blood thirsty thinkers out there will see it as appropriate retribution for the damage he has caused the world, chances are they aren't Iraqis.
Why is that? After all, he gassed the Kurds and treated the Sunnis like... well, shit. He suppressed whole swaths of his people. In general, he was a screaming asshole of the first order.
But wait -- how does he look now, three plus years into the occupation of Iraq? Before -- the country was fairly liberal religiously. Women weren't stoned for showing their faces. Kids went to school, went to college. There was water, electricity. The region was relatively (note I said RELATIVELY) stable -- they weren't dodging car bombs in the streets of Baghdad.
And now, thanks to the rather oddly speedy rush to hang him from the nearest gallows, we're about to make him a martyr to people who now see him as the lesser of two evils.
Even scarier is the point made recently that there may be a lot more Shite Muslims in Iraq then previously thought. Current thinking has it 4 Sunnis for every Shite, when it might actually be dead even.
In other words, if we thought that the <strike>secular conflicts</strike> civil war in Iraq was bad now, just wait until 2007.