If my country were small, and had lost several million of its citizens during WW2, I would consider Holocaust denial as the possible beginning of just another such awful period. And I'd think of it the same as shouting "FIRE" in a crowded theater.
You must learn from history. You can't say, "Oh, that will never happen again, we are all over that."
As far as I know, Hispanics have never denied the Holocaust happened.