syriacus -- yes I do. Here's what would have happened. We would declare Iraq a no-fly zone and watch from the borders. There would have been years of in-fighting between the sunnis and shiites. The herd would be thinned. Something stable would emerge.
If it posed a direct threat to us, we would strike those targets from the air. And so on and so on. It was a clean victory. One we should be proud of.
History argues the opposite. Take, for example, Afghanistan. There, with massive covert support from the US, the Soviet dictatorship was removed. Then, the US abandoned the region to sort itself out. This left a power vacuum that was filled by the Taliban and created the safe haven for Al Queda.
Politics, like Nature, abhors a vacuum, and out of chaos, it is rare that anything but a thug state emerges to make things stable. Given the history of Mesopotamia since the time of Abraham, what makes you think Iran, Syria, and Saudi Arabia would be content to let things settle out in the strategic breadbasket of the Middle East?