One of the reasons I support forcible regime change in Iraq is because I thought war was the best choice from a menu of bad options. To evaluate the merits of any decision, the costs and benefits must be weighed against the feasible set of alternatives [Why stress "feasible"?--ed. Because many (but not all) antiwar protestors tend to present alternative policy options, like the complete withdrawal of any U.S. presence from the Middle East, that could only have been dreamed up in Fantasyland]. Whatever misgivings I may have about the use of force, they pale besides the doubts raised by the material, political and moral costs of the next-best option -- containment.

To understand this, take a look at a short paper by Steven J. Davis, Kevin M. Murphy and Robert H. Topel, all affiliated with the University of Chicago's School of Business. They argue that the costs of containment -- measured in dollars and lives -- far outweigh the costs of war. (Link via William Sjostrom). Their key finding:

[W]ar and forcible regime change raise Iraqi welfare by 50 percent compared to containment – an enormous gain. At first,
it may seem surprising that war can lead to a huge improvement in human welfare. But, in fact, this conclusion is hard to escape so long as regime change even partly undoes the collapse in living standards under Saddam.

Their basic analysis is pretty solid. The authors start to stretch things a bit by factoring in the expected value from the "probability of a terrorist attack of the same magnitude as 9/11 by 5 percent per year" due to Iraq's continued development of weapons of mass destruction. Factoring in such a probability is acceptable, but the authors don't factor in the increased short-term probability that a war with Iraq will inspire other terrorist groups to strike at the United States. Still, this weakness does not fundamentally undercut their argument.