These are not Nazis--they are Trump and his supporters, being portrayed as Nazis, completely mischaracterizing the issues as they are today.
The idea that a US government would behave this way is abhorrent, and it also a terrible creative decision. All because the writers are butthurt that Trump won.
They are specifically a characterization of the Charlottesville white supremacists. Bluntly, whether they are meant to represent anyone or not in RL, they are close enough to the white supremacist militias that exist in my state of Kentucky and perform regular hate crimes.
Descendants of the actual KKK.
So I wouldn't waste any breath defending them since they're close enough to reality to matter even in caricature form. Like if you combined hippies and serial killers, it's a stupid idea but the Manson family still exists.