New York Times: When it comes to global warming, the United States has long been viewed as one of the world’s worst actors. American officials have been booed and hissed during international climate talks, bestowed with mock “Fossil of the Day” awards for resisting treaties, and widely condemned for demanding that other nations cut their fossil fuel emissions while refusing, year after year, to take action at home. Suddenly, all that has changed. At the global climate change negotiations now wrapping up in Peru,…