> ... Stoking grievances over the increased diversity of those countries ...

The underlying grievance is of course not over "increased diversity" per se but rather the long-term decline in civic attitudes. The progressive left expresses the exact same concerns in a different wording, by decrying the increased "marginalization and exclusion" that's seemingly entailed by such diversity. Guess what: they're all looking at pretty much the same thing.

> The underlying grievance is of course not over "increased diversity" per se but rather the long-term decline in civic attitudes.

I fail to see how the previous US president's complaints about people coming from "s*hole countries" and the exhortations from the Charlottesville rioters about how "Jews will not replace us" are grievances about "decline in civic attitudes". Try as one may to dissociate them, but these are the faces, words, and animating motivation of nationalism today.

The sad truth is that Jews have always been used as a convenient scapegoat for grievances of all kinds, and this is just as true on the left as on the nationalist right. For example, Marx famously blamed the rise of bourgeois capitalism on the Jews, and this casual anti-Semitism was picked up by many on the left.

> this is just as true on the left as on the nationalist right. For example, Marx famously blamed the rise of bourgeois capitalism on the Jews

Your argument is intentionally mixing "is" with "was".

Marx died 140 years ago, and there are no ethno-nationalist voices of significance on the left today. In the US context, after the civil rights movement of the 20th century those people left the Democratic party as the parties realigned themselves.

Today it is largely a right wing phenomenon, carrying forward the tradition of right wing ethno-nationalism that persisted from the previous century.