Saying that someone is a Nazi based on "Nationalist" being in the name as fallacious as those who would say Hitler was a socialist because "Socialist" is in the name. In reality, while Nazis and other fascists are inherently nationalist (almost always white nationalist in the US), someone being a nationalist doesn't necessarily make them a Nazi.
Nazis (it'd be more accurate to call them Neo-Nazis, but abbreviation is what it is) tend to believe in a big Jewish/communist/feminist (in the modern day) conspiracy; they use buzzwords like "Cultural Marxism", "Zionist", or "White Genocide/Replacement", and have slogans like "blood and soil", "hail to victory", and my favourite to laugh at, "Jews will not replace us". They make use of symbols considered occult such as the Black Sun and Nordic runes alongside the swastika, as well.
Know your enemy, for knowledge removes their power to intimidate.
