WITHOUT THE United States, does the decades-long effort to unite the globe in fighting climate change fall apart? That was the big question heading into a major international climate conference in Poland that wrapped up last weekend. It was the first such gathering since President Trump signaled the United States’ intention to pull out of the landmark Paris climate agreement. The result was better than pessimists expected — but also underscored how much will be lost if the United States steps further away from the global agreement. The 2015 Paris accord set a goal of keeping warming below two degrees Celsius. To get there, it asked countries to volunteer commitments to reduce their greenhouse-gas emissions. The commitments offered were not sufficient to meet […]