Greg Djerejian has written a long review and retrospective of Bush's first term-and-a-bit. He is particularly cogent on the subject of Saddam Hussein:
This is, in a nutshell, why war in Iraq was necessary. It was not made necessary by George Bush's actions, though he assuredly brought it forward. Rather, military confrontation in Iraq was the only way to preserve international law as a force for influencing the behavior of countries. The alternative to Bush's action was acceptance of a world in which "international law" would consist in resolutions, criticisms, diplomatic slaps at prestige, and perhaps, in extreme circumstances, economic sanctions (though the sad case of Darfur illustrates that such sanctions can generally only be imposed on countries with nothing to sell).
He was a unique danger, a sadistic strategic blunderer perched in the middle of one of the most volatile regions in the world. To not have gone after him in a post 9/11 world, after he refused to bow to the will of extant U.N. resolutions, would have been to give the lie to the seriousness of America's intent in a new and dangerous era.
These weak tactics are effective only when they are not needed. A dangerous regime is so precisely because it is not part of any "community of nations", and attacks on its standing in that community can have no effect. In dealing with such regimes, only two tools are available: force, and the threat of force.
The Clinton administration tried, in the main, to make do with only the latter tool. This is a form of free riding, expending the credibility earned with blood; and, inevitably, it steadily lost its effectiveness. In the long run, the threat of force cannot be detached from the use of force. The credibility lost in the attempt can be regained in only one way.
If not Iraq, where would the next war have been fought? What bloody acts would have been carried out, within and across their borders, by nations fearing no meaningful reprisal? I, for one, am thankful not to know the answers to these questions.