Hitler had a deep hatred of the Jews and, when he gained the power, he began immediately to find ways to to harm them and eventually destroy them. He defined Jews very broadly as anyone of even slight Jewish heritage. You are a Christian pastor and your family has been in Germany for three centuries but your grandmother was half-Jewish? Then you belong in a gas chamber.
Hitler was a morally twisted man who needed only power to enact his hatred.
You are a judge born in Indiana to parents who immigrated from Mexico? Then you are Mexican and you cannot be the judge in any case by or against me, says trump, who has learned his political and moral views from Hitler.\
If there were just one word to describe the leadership style of Hitler/trump, is would have to be intimidation. Once they decide you are an enemy (i.e., not subservient) you will be intimidated, threatened, fined, jailed, destroyed. . .all at the whim of the tyrant.
Hitler was popular at first, as trump is so far in America. Germany woke up too late, just as is going to happen to some Americans.
Hmmm, I wonder what George Santayana meant when he said, “Those who cannot remember the past are condemned to repeat it”?