When the people vote against democracy.The social media hashtag #NeverTrump first appeared in June 2015, days after Donald Trump announced his presidential candidacy. For the balance of that year, social media derision attracted less attention than Trump himself, mostly due to the widespread belief that Trump’s campaign was self-extinguishing, which argued against pointless efforts to bring about an already inevitable defeat. In election cycles since Ronald Reagan’s 1984 landslide victory, unlikely protest candidates for the GOP presidential nomination—Pat Robertson, Ron Paul, Herman Cain—had briefly surged in the polls, only to give way to a conventional politician who ended up as...