Expressions like Italian-American and Irish-American don't distinguish between the USA and Canada and Mexico either. Or for that matter Argentina. So would I be right in assuming you object to all these expressions, John. If you do, fair enough. If you don't, what's the relevant difference? (The fact that Africa is a continent rather than a country is not in any way a relevant difference.)
....................................................

I wasn't suggesting that "black", as in "Black Americans" is something to be reasonably objected to - but "the American black" is just not the same. I don't think many people would feel comfortable with "the American white" either. It sounds too like a breed of livestock - a chicken maybe, such as the Rhode Island Red. Or maybe one of Harry Potter's dragons, such as the Common Welsh Green or the Hebridean Black.

We just don't normally talk about human beings in that way, and in consequence it seems to send a message, no doubt inadvertently in this case.