President Trump is a turbocharged communicator whose message isn’t always to everyone’s taste. Yet in India on Monday he made a speech before 110,000 people that was uncharacteristic. Not only was there nothing in it for his detractors to pounce on, but he also took an opportunity to defend liberal values.

The speech included plenty of Mr. Trump’s typical chest-thumping. “We make the greatest weapons ever made,” he thundered. “We have the greatest economy ever in the history of the United States,” he boasted. But put aside...