In response to my post below on his op-ed comapring the costs of the Kyoto Protocol with that of the war in Iraq, Cass Sunstein e-mails:

Despite the Post's misleading subtitle ["If We Can Fund the War in Iraq, Why Can't We Fund the Kyoto Protocol?"], and probably some unclear writing on my part, I meant only to make a cost comparison, and not to endorse the Kyoto Protocol, which is (in my view) unjustified in light of the cost-benefit ratio. It's clear that the original cost projection for the war ($50 billion) was much too optimistic, and it's not at all clear that the Bush Administration gave an adequate explanation for rejecting Kyoto — but everything turns on the cost-benefit comparison. My purpose was just to compare costs, which seems to me worthwhile even if only a part of the picture.

This is an entirely fair point. Prof. Sunstein has posted some additional thoughts on the University of Chicago faculty blog as well.

UPDATE: Professor Bainbridge adds his thoughts on the subject here.