As horrible as MAGA support of Trump’s evils has been, it doesn't touch what the Nazis did. Would he be willing to do everything Hitler did, given the chance? Sure. But he hasn't had the chance yet, and his time is rapidly running out as his health deteriorates.
Also, there is no MAGA party that people can join, and no one is required to tell anyone else who they voted for in this country, because our elections operate by secret ballot. Not all of his supporters are Republicans, and not all Republicans are Trump fans. And even if one equalled the other, identifying all the Republicans would not be easy.
Voter registration would supply party affiliation information in some states, but not all states ask voters to indicate their partisan affiliations on voter registration forms. My state, Illinois, is one of those. (More info on this topic can be found here: https://ballotpedia.org/Partisan_affiliations_of_registered_voters)
Granted, a lot of Trump voters are easy to recognize, but without a reliable way to verify not only party affiliation but who actually voted for the Orange Hellbeast, there is no way to accurately identify all of his supporters or their level of loyalty. And besides, ain't nobody got time for that! We'll be too busy putting this country back together to spend time and money trying to figure out who all the Trump voters are so they can be punished accordingly.
Even in Germany, all the registered members of the Nazi party weren't punished for being Nazis, and not all card carrying party members were complete monsters (for one example, see https://en.wikipedia.org/wiki/Oskar_Schindler).
Some leaders were tried for their crimes and sentenced accordingly, but many of the rank and file members were not. More info: https://www.theholocaustexplained.org/survival-and-legacy/postwar-trials-and-denazification/
In short, there is no reliable or just way to identify and punish every Trump voter even if we wanted to (and I for one question the advisability of that). I'm all for punishing those who did illegal things (like the ICE thugs and thise who gave them their orders, for examples), but it is not a crime to vote for a horrible candidate or support a horrible president in this country, and God help us all if either of those things ever becomes a crime.
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