The Nazis were, first and foremost, Socialists, and Donald Trump is not. The Nazis also claimed to be “nationalists”, but that was not their main emphasis, as they regarded themselves to be the nucleus of a worldwide empire, the Reich that would stand for a thousand years.
The Democrats have been quick to conflate the “nationalism” of the Nazis with the nationalist policies of Donald Trump, but clearly there are two very different interpretations of the meaning of “nationalism”. As postulated by Adolf Hitler, “Ein Volk, Ein Reich, Ein Fuhrer” was essentially a pledge of allegiance to a totalitarian dictator, with a modest nod to “Vaterland”.
The nationalism of Donald Trump is encapsulated in “Make America Great Again”, a reference to the historical importance of the experiment that was and is the United States of America has for the world as a whole. The USA is a land of high social mobility and few forbidding class distinctions, perhaps unique in the world, and it got that way by embracing a great range of personal freedom, a right not enjoyed by the vast majority of the inhabitants of earth.