Not every cultural clash should be compared to the Holocaust. There are plenty of historical examples of societies that got eaten from within when they couldn't maintain their culture in the face of aggressive foreign ones.
Today we have history to tell us where things could go. If we don't allow comparisons to the early stages, might we unwittingly make later stages more likely?
There's an implicit valuation of culture in this statement. Most cultures throughout history melded and adapted to other cultures, both in little and big ways. Xenophobia about cultural invasion is also throughout history, but the reality is that dominant cultures are never "pure" and diversity of culture was actively censored and/or ignored by some historians for a long time.
Damn right.
Our precious "British" culture is a Franco-Germanic-Nordic-Celtic-Romano-Pictish-Jutish-Afro-Indian-Sinesian and god only knows what else fusion. They should teach Bayeux, not Carta.