Part of my family came over from Germany in the 1800's and immediately changed their names to blend in. How's that not assimilating?

It is. And there are plenty of individual instances of that happening, both historically in the 1800's in the U.S. and throughout Europe.

But that's not what we saw in this country across the population. Instead, the Germans (and the Irish and the Italians and all the other prior waves of immigrants) held fast to their language and tradition and religion, forming ethnic enclaves and setting up all sorts of institutions to preserve their particular identity. The exact same thing that modern critics excoriate as unworkable in the European context (or the modern American context). It happened here, too.

Again, missing the point, which was "What about the UK caused Reform to do so well in the council elections?"

I was responding to your claim that America was different - that our waves of immigration involved people who were choosing to forego their linguistic and culturally identity. That "immigrants to the US melted their culture in with the existing one, creating the America we have today. Everyone adapted. People came to the USA to become...Americans." That's not what happened here.

That's not a distraction from your point. I have no doubt that anger about immigration may have played a part in Labour's losses. As with Europe today, large waves of immigrants here in the U.S. also caused political upheavals, caused political parties to win and lose elections, etc. Native dissatisfaction with large numbers of immigrants is an important and significant political factor.

But I think you're wrong in suggesting that things were different here - that our successive large waves of European immigrants somehow conducted themselves differently, that they came to this country in order to become Americans in ways that current migrants to European are not intending to become Germans or Danes. That's an ahistorical and incorrect view of our past.