Both my native country, India, and my adopted country, America, are liberal democracies that are right now in the thrall of right-wing populist demagogues -- Prime Minister Narendra Modi in India's case and President Donald Trump in America's. Few would deny that between the two, Trump is the crazier one -- a showboat with impulse control issues. Modi, by contrast, a humble tea stall owner once, is a veritable picture of discipline and restraint. Yet Modi, who got re-elected by a landslide last month, is potentially more dangerous because Indian democracy lacks strong institutional checks on his illiberal ambitions. In...