Grist: On Tuesday night, when news broke that the U.S. and China had jointly announced plans to limit greenhouse gas emissions, I predicted that Republicans would argue the terms are unfair. American emissions have already declined by 10 percent from 2005 levels, and we have already committed to reducing them further to 17 percent by 2020. Now Obama has added another, more ambitious goal for 2025. China, meanwhile, has until 2030 to peak its emissions, not even cut them, and to generate 20 percent of its...