We are talking here about 40-50% of the American electorate not some fringe maniac. If you think those people's opinion should be shunned than your world view seems very restricted to me.
Trump is obnoxious but Stalinist purges are not an answer for it.
millions of illegal immigrants, as a candidate to immigration myself, following the rules, I see no problem with that.
I'm not equating Trump and Hitler, btw. But Hitler proves that being mainstream means nothing.
Separately, it is also my perception that both men's source of power are somewhat similar. They both have supporters that want an aggressive, authoritarian leader to change things drastically because the current direction isn't working for them. I think that's a dangerous thing to wish for.
It means that you better take the position serious and engage in a real discussion. By labeling one side good and the other evil you just drive both sides more into towards the extremes.
Not the same thing at all.