Gary Cohn, the President’s director of the National Economic Council and the highest ranking carbon tax advocate in the White House, resigned yesterday amid a disagreement with his boss over steel tariffs. Nicknamed “Carbon Tax Cohn” by ousted presidential advisor Steve Bannon, he lobbied heavily for the U.S. to remain part of the Paris Climate Accord.

“Coal doesn’t even make that much sense anymore as a feedstock,” Cohn—also dubbed Globalist Gary—said last year. He is one in a string of policy experts to recently announce departure.