Is the battle to contain global warming now lost?

With the election of Donald Trump, it certainly looked that way to many of the shellshocked diplomats gathered in Morocco earlier this month at the first climate summit following the breakthrough agreement in Paris last year to contain greenhouse gas emissions.

During the campaign, the president-elect of the world’s second largest polluter claimed that climate change is a hoax, threatened to drop the Paris accord, committed to kill the Clean Power Plan at the center of President Obama’s emissions reduction strategy, and promised a new dawn for the fossil fuel industry.

Don’t give up just yet. True, international diplomacy will become more difficult as China and India weigh their own energy policy commitments in the light of the possibility that the United States will walk away from its promises. But President Trump’s climate policy — or his lack of one — could work out in surprising ways.

Ted Nordhaus and Jessica Lovering, in a report published on Tuesday by the Breakthrough Institute, pointed out that real progress on reducing carbon in the atmosphere has been driven so far by specific domestic energy, industrial and innovation policies, “not emissions targets and timetables or international agreements intended to legally constrain national emissions.”