History doesn't repeat itself. Human behavior patterns repeat themselves, because humans are deeply conditioned animals, but history doesn't repeat itself. Anyone who says it does is confused about how time works.
Consumers of mainstream culture have been trained to watch out for the next Hitler the way evangelical Christians are trained to watch for the second coming of Jesus. References to Hitler are ubiquitous in movies, television, literature, and of course in political discourse, and understandably so; he is the clearest, purest example of evil in living memory. A genocidal dictator leading humanity into world war with the explicit agenda of totalitarian global domination is indeed as stark an example of an evil human being as you could possibly imagine, and serves as a philosophically unassailable "NOT THIS WAY" sign for our species. The saturation of our culture with that sign is why Godwin's law ("As an online discussion grows longer, the probability of a comparison involving Hitler approaches 1") is a thing; any time you want to tell a stranger that their ideas could lead in an undesirable direction, it becomes increasingly tempting to throw up the "NOT THIS WAY" symbol that Adolf Hitler has come to represent.
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