Remember when Bush and his allies would ask opponents of the war, "Are you saying that we would have been better off if Saddam was still in power?" And, of course, no one could answer, "Yes."
An affirmative answer to that loaded question looks a lot more credible now, doesn't it?
Look at it this way: No one but George Bush (and maybe Deadeye Dick) thinks that American military force can make a significant difference in the situation, at least not for the long (or even medium) term. There is no force in sight that can keep Iraq--except for the Kurdish provinces in the north--from sinking into a state of anarchy that will make a real civil war look like an improvement. The main contending forces are religious denominations, have the faith of true believers. (I don't mean that to label Muslims--true believers in all religions share the same characteristics.) If there is a force for Iraqi national identity, or even for peace, it is invisible.
So, when the American forces and our allies leave, what alternatives are there? The best of the ones that are at all plausible would be the early emergence of a strong man, whom we may hope to be a lot less brutal and bloodthirsty than Saddam. Much more likely is a lengthy period of the kind of brutality that we saw in the former Yugoslavia. A massacre along the lines of Rwanda is a real possibility.
Are you still so sure that Iraq is better now than it was under Saddam?
I don't mean by this that the United States should have let Saddam and his fellow killers should have their way with the country, and we did not. We protected the Kurds (the only group to organize an effective counterweight to the regime) for more than a decade. The no-fly zones enforced by British and American aircraft crippled Saddam's ability to threaten his neighbors, and humiliated him. What we never did, however, was to organize an effective rebellion outside of the Kurdish areas; indeed, having encouraged the Shi'ites to rise in 1991, Bush senior cut their legs out from under them by holding back on the support they had been promised.
A rebellion would not necessarily have led to a stable regime; Afghanistan in the 1990's is proof of that. But the struggle could have weeded out the incompetent and perhaps developed a sense of common purpose that might have served as the glue for a new state.