I’d say that you need to have political views in the first place in order for them to change based on whatever reason, and well, Trump’s views aren’t exactly terribly complicated. He just says whatever nonsense comes to mind. I’m confident he didn’t change his mind at all, because in all likelihood he’s never known what the hell he’s talking about. He doesn’t understand politics or economics, he’s almost completely ignorant of current events and mostly ignorant about the world outside the US. All he has is catchy slogans and a “fake it till you make it” approach to things.