I am generally a bit cynical about politicians, which perhaps comes from meeting too many of them. However, I have also known a lot of very wealthy people. I know that Trump didn't become president to get richer, and also not to get access to interns like Hillary's husband since billionaires have that option already. When he said that he "had to do it", I believed it was patriotism. The mystery was what he wanted to accomplish, and I imagine a lot of people are surprised to find that his campaign promises were all true.
Agreed! But even his goals were no mystery; he had been saying the same things about other countries taking advantage of us economically since the 1980s.
Donald Trump 1980 Interview with Brokaw, age 33
Trump on Oprah discussing foreign trade in 1988
Donald Trump Testimony before Congress on Economic Recovery, 1991