The Trump = Hitler shtick is just confirmation bias in peoples minds employed by the Clinton Campaign to whip up fervor in the mindless zealots of the far left. I don't know how a man who has never said anything about any race could be defined as Hitler but the Clinton campaign found a way and now liberals are primed to see anything Trump does as Hitler 2.0.
Honestly it says more about the people who fall for this than anything else but hey, useful idiots.