Former president Donald Trump, speaking this weekend at the gathering of the Faith & Freedom Coalition, returned several times to the subject of the U.S.-Mexico border. Trump described migrants crossing it as “tough” and said that he told his friend Dana White, the president of the Ultimate Fighting Championship, to enlist them in a new version of the sport. “Why don’t you set up a migrant league and have your regular league of fighters. And then you have the champion of your league, these are the greatest fighters in the world, fighting the champion of the migrants,’” Trump described saying...