Donald Trump has signalled the end of US leadership on climate policy, with potentially unpleasant consequences for America's economy, security and diplomatic standing.
Trump has promised to abolish Obama's Clean Power Plan and back out of the Paris climate accord. But business could become a key firewall that won't let Obama's sustainability legacy die.
The halls of the Marrakech climate summit have been filled with fearful talk about Donald Trump's presidency. But there is hope that the Paris climate treaty can weather the political storm.
President Obama's new targets for emissions from electricity are a crucial step towards a credible US climate policy. And where the United States leads, others are more likely to follow.