Vox has an excellent article that explains some of the sociology behind all this, showing the personality profile of authoritarians and how fear is a driving force in bringing their dark side to light. One of the interesting things they mention that is easily lost is that Trump isn't even the real problem. The real problem is an American people who espouse an ideology that creates and supports people like Trump. I want to say that he doesn't represent the Republican party, but from the people's point of view, he does (or at least more than half of it). And that means that even if Trump can be defeated, we will see more people like him in the future, because that's what the people are demanding. What we're seeing is a people who are so scared that they want a strong leader, one who will stop at nothing to ensure their security.