CLAREMONT, CALIFORNIA — Can U.S. President-elect Joe Biden walk and chew gum at the same time? If walking is managing domestic pressures, and chewing gum is pursuing a balanced foreign policy, the answer is far from clear. The tension between bipartisan calls to contain China and the imperative of cooperating with Chinese President Xi Jinping on climate change is a case in point. Biden plans to marshal a broad alliance of democratically-minded Pacific and European countries to check China’s expansionism. In Xi’s view, however, China may be able to use the promise to cooperate on climate change as a source of leverage with which to thwart Biden’s containment strategy, especially in light of Republican opposition to climate action and hostility toward China. The stakes could not be higher. Humanity faces a truly calamitous future if the world’s two largest economies — and largest CO2 emitters — don’t commit to cooperating to address climate change. And yet the grim