It's not “me and my ideological tribe against Hitler and the other guys for him.” It's more “pretty much our whole generation against Hitler because we know from history where that stuff can lead.”
You seem to think that Hitler and his movement are some kind of isolated incident peculiar to a particular moment in history. There is nothing new under the sun. This was true 70 years ago, 700 years ago, 7000 years ago. Hitler was Evil. Nothing more, nothing less. Moreover he was Evil long before he ever rounded up on person or fired up one oven. To say that the modern epitome of Evil is somehow isolated from modern day men and that the cowardice that allowed him to come to power is vanished from the human psyche thanks to the horrific example provided by Hitler is to demonstrate an absolute ignorance of History and Human Nature.
It's pretty much a given that people nowadays condemn past evils. Very few people now would give their assent to brownshirts in the streets or gas chambers for minorities.
When evil surfaces again, most likely it will be in a different form, an new package, that may be hard for people to recognize.
There's something very self-congratulatory about people who identify their present-day political opponents with Hitler. Who can say that when political evil surfaces in a new guise they'd be any more likely to recognize it than other people?