It might usually manfiest as that or you're picking out the most superficial parts of people's identity to criticize. It's just not how I and others view it when we think about where the people who made us come from.
Or, to put it another way: your criticism is tacky and vulgar. Perhaps what you're describing is "cosplaying" but that's not how immigrant communities see themselves. I do in fact know the perecentages of my national makeup but pizza and beer aren't how I celebrate that. Nobles know their ancestry down to the smallest detail, is somebody really tacky for knowing that technically they are 1/4th Italian? I don't think attacking somebody's identity is ever fair; it costs you nothing but is everything to them.
Like many Americans, I am from a European immigrant background. For what it's worth, I have spent a lot of time in x-land, and I speak x-ish. But I am an American. My ethnicity is mixed. I grew up in America. You would never know my heritage unless I told you, which I probably never would. Because I hate hearing the "Me too! I'm x-ish too!" spiel from another American who can't even pronounce their own surname correctly.
I think that a lot of people are irked by the sheer inconsistency of the American culture: celebrate your immigrant heritage at the same time you protect “your” American land and keep those pesky immigrants out. Not personal.
There's a depth to what you're saying that I don't think you're truly aware of..."flooding the block" -- or the mass importation of immigrants to build a political machine -- has been part of my country's politics since the Tammany Hall days (political machines). Tale as old as time in the US and it's one of the reasons why there's so much skepticism. Like what you said here, we KNOW how this works because at some point we were the Irish\Italian\or Mexican that got shipped in. We're not blind to party politics and ginning up house delegates or patronage politics.
Really so its okay if a Canadian, Australian or New Zealander does it?
It wouldn't be. But they never do it, so I don't have to worry about it.
> that's not how immigrant communities see themselves.
Whoa, who's talking about immigrant families? Immigrant families came from somewhere else. That's their identity, because it's where they came from. But if your family has been here for a few generations, then I have news for you: you're not immigrants!
> I do in fact know the perecentages of my national makeup. Nobles know their ancestry down to the smallest detail, is somebody really tacky for knowing that technically they are 1/4th Italian?
The game of percentages is absurd to begin with. It's one thing to know you have some ancestors from Japan. It's another to say "I am 12.5% Japanese!" What the hell does that even mean? When noble families recognize their ancestry, first off, they don't make ridiculous claims of percentage. No nobleman says "I am 1/16 Catalonian". They'd laugh at you. "You mean to tell me your culture is 1/6 Catalonian?" Second, they don't identify with the culture of an ancestor if it has no presence and reality for them. The British royal family has German roots (and like all European royal families, a complicated web of ancestry spanning virtually all of Europe in some way or another), yet they don't claim to be German or Hessian. It would be absurd. They're the British royal family, and much of them have been the British royal family for some time!
(I do recognize cultural identity as complex, of course, more complex than how many people see it, but it's complex when the cultural dimensions are actually real, not fabricated by the imagination.)
> I don't think attacking somebody's identity is ever fair; it costs you nothing but is everything to them.
But it's not their identity. It's a pretense. If some distant ancestor's cultural origin is everything to someone, then you're proving the absurdity of of the whole thing.
Like I say, it's a socially-accepted form of cosplaying.