@jay @goatsarah While I agree with her take somewhat, I also think this is extremely easy to miss for us Europeans. Yes, the boundaries of whiteness are not identical in Europe (e.g. the ironic "discrimination" against Italians is funny to Americans but less funny in places like Germany where they are seen as non-white) but that doesn't mean the mode of discrimination doesn't exist here. Our understanding of whiteness is more balkanized but it's still there and at the core of this oppression and anti-Blackness is widespread even if there may be fewer Black people around.
Heck, despite the racism against Eastern Europeans it's trivial to see the difference in how e.g. Germany treats white Ukrainian refugees compared to how it treats brown refugees. There was literally a public discourse around how the existing shelters were undignified and inadequate for Ukrainians when they were apparently perfectly sufficient for Syrians and North Africans.
Yes, whiteness is a social construct but it's also defined by exclusion. It's not literally about skin color, it just often aligns with it. But as the recent cases of Latino/Hispanic white supremacist violence in the US have shown, this complexity is not unique to the US.
As for Europe's history of colonialism: just because we were so racist we didn't want to bring most of the slaves to Europe that doesn't mean we heavily promoted slavery and benefitted from it. Just look at Belgian rubber plantations to see how much pain this caused.
You can't export social justice discourse 1 to 1 from the US to Europe but that doesn't mean it doesn't apply. It's not an exact match but it doesn't require many adjustments. We're just leagues behind when it comes to reflecting on our history of these issues. That's not something to be proud of and it's not the fault of the US.