Romney on Cap on Emissions

Romney lost a lot of credibility on the climate issue when he suddenly pulled Massachusetts out of the Regional Greenhouse Gas Initiative in 2005, a cap-and-trade system for the Northeastern states. And he hasn't gained it back. These days, he's only for a U.S. carbon cap if it's part of a global cap-and-trade scheme. But what's interesting is that his adviser, Gregory Mankiw, is a staunch proponent of a carbon tax over any cap-and-trade plan.