Pure speculation but, given his age, there is a good chance he saw Trump and American Conservativism as the Nazi cover operation it is and wanted to fight his own WW2 against overwhelming evil. College is about the time we learn the world doesn’t run like a small town and massive things can exist like human rights abuses and amoral politics. He probably felt Tlthat shock and frustration that the world continues to be ruthless because and in spite of us.

Then he saw a figurehead for the alt right and decided to be the change he wanted to see in the world.