Christopher Hitchens says yes
Linda J. Bilmes and Joseph E. Stiglitz say no
BTW, I'm in the middle of reading Hitch's book God is not Great, and I think I agree with almost everything he writes therein. On the Iraq war however, I have been convinced for a long time that it has not been worth the price. Maybe because I agree with him so much in his book, this article propted me to redo my calculations, which I fully admit cannot begin to hope to really know the true costs of everything. I still think that it probably was not worth it, but maybe I'm a little less certain than I used to be. I do think that Hitchens makes as good an argument as can be made for his proposition. Nonetheless, knowing what I know now, I'm pretty sure I wouldn't be for it if transported back to 2002 or early 2003. Then again, maybe in another 5 or 10 years things will look still different. God only knows the true answer.