New York City mayor Michael Bloomberg just gave a bombshell speech here in Seattle calling for a federal carbon tax. (Full text of the speech is here, scroll down.)
First off, way to go, Bloomberg! (In fact, Sightline Institute's Anna Fahey has written about Bloomberg's awesome framing.) But now, with my researcher's hat on, I think it's worth it to clarify a few things.
While many of Bloomberg's arguments in favor of a carbon tax were spot-on, he made some very selective criticisms of cap-and-trade programs -- criticisms that seem targeted at only the worst way of doing it. As far as I can tell, Bloomberg completely ignored the right way to do cap-and-trade, which starts with auctioning the credits, not giving them away for free.
So as a service for wonky readers, here's a little primer that I whipped up this morning: