At least from my perspective this has been an ongoing problem for many years now and I would refer you to Godwin's law.
There is this weird sort of mystique about Hitler and the Nazi Party that keep people entranced that it was "pure evil" rather than a decade-plus political process taking place in a very unique time of history with many other actors in play. You can't use any sort of "slippery slope" argument because of course those don't exist. The fact that you can trace elements of both WW-I and WW-II to at least the mid-1800s in terms of holistic world upheaval doesn't even get mentioned. There doesn't seem to be many students of history these days.
Instead what we get is almost fantasy horror and when you try to make serious political arguments they are just dismissed. I mean, it can't happen here because unicorns don't exist either. I also find it troubling that many people have no appreciation for Marx, Lenin, Stalin, and Mao in light of the millions lives that were destroyed after WW-II. Some very horrific acts occurred in the 20th century and debating rather than dismissing these issues seems like not only a good idea, but probably essential if peace and humanity are truly desired.