Pope Francis has shown himself to be pretty much just a leftist dope.
What has happened here, I think, is that the election and reelection of Barrack Obama has shown the world that the population of the United States is so impenetrably stupid and so susceptible to media influence that many self-important and some actually-important foreign figures are emboldened to try their hand at influencing American politics.
A secondary causation is the deep visceral fear the left has of Trump, similar in many ways to the rabid pronouncements against Ronald Reagan when he was running.