Godwin’s law (or Godwin’s rule of Nazi analogies)[1][2] is an Internet adage asserting that “As an online discussion grows longer, the probability of a comparison involving Nazis or Hitler approaches 1”—​that is, if an online discussion (regardless of topic or scope) goes on long enough, sooner or later someone will compare someone or something to Hitler or Nazism.
Sometimes the analogy fits and Trump goes to a lot of effort to constantly flirt with that line. I also have never heard him denounce David Duke or the neo Nazi website the daily stormer which both have endorsed him.
Goodness law is fine. However, indiscriminately sending jackboots from house to house willy nilly in the middle of the night is exactly what the Nazis did. It also happens to be unconstitutional.