This is my take on Trump. He initially became popular with his “Build the Wall” gimmick. So, he was triggering people’s survival instincts, fueling fears that the refugees coming across the southern border was an “invasion” of people that are going to take something from them. That is the essence of populism.
What is never explained by the corporate controlled mass media, is that the root problem is globalization. It is globalization that impoverishes cities in America through labor arbitrage (sending the jobs to China), creating an increasing inequality in America, that fuels the populism (“they want to take everything away from me”). It is also globalization that loots the resources of poor countries, taking the land of its citizens through fraud and violence, who then go into cities where there is no work, and then in desperation, follow their stolen resources to America.
The corporate mass media then fuels the fighting between the victimized groups, which is profitable to them, taking the focus off of the real culprits – the globalist ruling class.
A good book that goes into the depressing details is “The Case Against the Global Economy” by Jerry Mander.