The Pope is politically biased.
Why is it Pope Leo likes mouthing off at everything Trump does, but he totally ignored the Iranians gunning down thousands of their own people?
Trump doesn't think the Pope's criticisms are justified.
However, I don't think this is as big a deal as the media is making it out to be.
In my opinion this is usually what Popes say about American presidents.
They never like anything America does.
Trump says the Pope is a liberal and that's his major beef with him.