While I agree in general with the analysis presented in this article, I think predicting the next few years is more problematic due to a greater number of influential variables. First of all, Trump himself: an infantile halfwit creature who lacks any form of spine. He will bluster with glee if he's carried to power on the shoulders of others, but lacks the capacity to lead a coup. So we can certainly imagine cynical far-right politicians using him as their totem, much as far-right politicians imagined they could use Hitler back in the 1930s in Germany. But unlike Hitler, Trump is a whining coward who will always run and hide under the bed whenever he feels afraid.
Next up comes the question of whether "progressives" could unite against the far-right. This seems highly doubtful, as leftists always focus on tearing each other apart for imagined infractions of whatever happens to be Politically Correct at any moment in time. They expend far more energy on these internecine wars than on opposing the real enemy; meanwhile the far right (the US Republican Party and the bizarre collection of witless religionists who strongly influence it) is concentrating entirely on power by any means available. Thus it seems unlikely a civil war of the kind that tore Spain apart will occur in the USA. It's more plausible to imagine thousands of eager virtue-signaling placard-waving progressives being shot by AR-15 toting rightists than to imagine a true gun battle between them. I suspect more deaths will be caused among the flabby halfwit neo-fascists by negligent discharges than by rounds coming in from the opposition.
What is certain is that "patriots" will eagerly lap up all the divisive content created by Russia, North Korea, and the many for-money freelance sources, and thus feel a warm glow of righteousness as they continue their destruction of the nation they think they love.
Because that's what morons always do, in the end.