Pope Francis and Donald Trump have been circling each other for a while now. Ever since Francis first visited the U.S., during the early days of Trump's presidential campaign, it's been hard not to ponder what they make of each other. Sometimes they've invited the comparisons: “A person who thinks only about building walls, wherever they may be, and not building bridges, is not Christian,” Francis told reporters after visiting Mexico last year, not mentioning Trump by name -- but inevitably bringing to mind one wall in particular. Trump, for his part, has swung between suggesting the Vatican is weak on terrorism and praising Francis for having “a lot of energy.”