The mud-colored air that blankets Chinese cities these days is bad for the people who live there. It may prove unhealthy for U.S. coal producers, too. Intense opposition on the U.S. West Coast, over climate change , rail congestion and damage to Native American fisheries, already is blocking new export terminals designed to ship coal across the Pacific Ocean . Now, China — which consumes almost as much coal as the rest of the world combined — is accelerating a planned switch to cleaner fuels, including a possible cap on carbon emissions and limits on new coal-fired plants. Even if such changes don’t occur as fast as environmentalists might hope, Chinese President Xi Jinping plans to scrap the economic strategy that spawned coal-eating steel plants in every province. Mounting anti-coal sentiment in China and the U.S. imperils the ambitions of companies like Peabody Energy Corp. (BTU) and Arch Coal […]