Something unexpected is happening in the Republican presidential field. Leading GOP candidates once denied the reality of manmade climate change, but now they seem to be softening their posture and subtly embracing it. Take the case of Donald Trump. His denial of climate change has been a centerpiece of his act for years. In tweets between 2012 and early 2015, he called climate change a "con job," a "canard," a "hoax," "bulls**t," and a concept "created by and for the Chinese in order to make U.S. manufacturing non-competitive." But as his political star has risen, he’s changed his tune on...