EPA chief: US-China climate deal is a 'big step forward'
04:03Andrea Mitchell talks to Gina McCarthy, the chief of the Environmental Protection Agency, about the U.S.-China climate deal, as well as the upcoming Senate vote on the Keystone Pipeline.
Andrea Mitchell talks to Gina McCarthy, the chief of the Environmental Protection Agency, about the U.S.-China climate deal, as well as the upcoming Senate vote on the Keystone Pipeline.