Meh, it’s one thing to disagree with how to fix the problems in the world, it’s another thing to glorify past atrocities or just outright deny them. If someone starts denying the holocauss, I’d just ignore them, and report. Same with denying atrocities committed by any other groups of people. There’s no arguing with these people. Argument is for topics like:

Which is a better pet: Cat vs Dog?

Representative or Direct Democracy?

Unitary vs Federal?

FPTP or Ranked Choice?

Presidential system vs Parliamentary system?

And arguing whether some groups of innocent people should be summarily executed or not is not a valid discussion. Arguing about whether history happened or not when there is already more than enough evidence isn’t a good topic to debate about.