Why shouldn't I change my mind?

It was perfectly honorable to agonize over the wisdom of the war, and in many ways admirable that people on the left, such as Christopher Hitchens, George Packer, Michael Ignatieff and Jacob Weisberg, supported intervention. That position was much easier to defend in early 2003, however, before we found absolutely no stocks of chemical or biological weapons and no evidence of an ongoing nuclear weapons program. (I know that many on the left believe that the prewar estimates about Hussein's weapons of mass destruction were all a deliberate fraud by the Bush administration, but if so, it was one in which the U.N. weapons inspectors and French intelligence were also complicit.) It was also easier to support the war before we knew the full dimensions of the vicious insurgency that would emerge and the ease with which the insurgents could disrupt the building of a democratic state.

But in the years since then, it is the right that has failed to come to terms with these uncomfortable facts. The failure to find WMD and to make a quick transition to a stable democracy -- as well as the prisoner abuse and the inevitable bad press that emerges from any prolonged occupation -- have done enormous damage to America's credibility and standing in the world. These intangible costs have to be added to the balance sheet together with the huge direct human and monetary costs of the war.

Secretary of State Condoleezza Rice recently admitted that the United States made numerous tactical errors in Iraq, but she insisted that the basic strategic decision to go to war was still as valid as ever because we foreclosed once and for all the possibility that Iraq would break out of sanctions and restart its WMD programs.

But we now know a lot that throws that fundamental strategic rationale into question.

The Iraq Survey Group and the U.S. military have released hundreds of pages of documents on Iraq's prewar WMD programs showing that, at times, Hussein believed he possessed biological weapons that didn't exist and that, at other times, he led his most senior commanders to believe he had WMD capabilities that he knew were entirely fictitious. His government was so corrupt, incompetent and compartmentalized that it is far from certain that he would have succeeded in building a a nuclear program even if sanctions had been lifted. Nor is it clear that a breakdown of the sanctions regime was inevitable, given an energized United States and the very different political climate that existed after 9/11.