Nazis murdered millions, including many Americans, during the 1930s and 1940s. They do not deserve a seat at the table of any "free speech" debate. They don't get to represent "the white race" any more than radical Islamists get to represent "the Arab race".
I'd happily tell them that Hitler was a punk, his views are perverse and anyone wishing to celebrate the man deserves prison.
Further, Trump needs to forcifully disown these people and condemn them as traitors to their race and to their country. The Left is going to try to continue to tar him with this alt-right crap until he denounces it more completely than he has up until now. Just like Obama had to disown Reverend Wright in order to have credibility with the rest of the electorate.
Either you don’t get the whole 1st Amendment thing or you don’t care to see it protected. Either way is shiver me timbers scary! I do not understand where you are coming from. Happy Thanksgiving.