Here's the difference: Trump is a jingoist: He thinks America is morally superior and other nations are morally inferior. He has an "us vs. them" mentality. He preaches bigotry and intolerance. His idea of making America great is to exclude the immigrants that made America great in the first place. He is also a science denier, which is a separate issue, but means his policies are based on magical thinking rather than on reality. He wants to take jobs back from other countries that he feels they "stole" from us, even though it was American businessmen like himself who sent those jobs overseas in the first place.
Elon Musk is a humanist. He wants to make the world a better place for all its people. He wants to build manufacturing here in the U.S. to benefit America, not to try to "take back" jobs. His vision of the electrification of transportation has a view of reducing carbon emissions and slowing the coming disaster of climate change, which affects the entire world.
Musk wants to build. Trump wants to tear down, and to isolate America from the rest of the world. Musk wants to make America greater than it is in a manner that improves the whole world. Trump thinks that to improve America he needs to decrease the rest of the world. It's as if Trump thinks he can raise the Atlantic ocean by lowering the Pacific ocean.
