I look at it this way. I have multiple ethnoracial identifiers you could use, and most of them are capitalized. There's American, of course, and for me there's also Jewish and Swedish (I'm a mutt). All capitalized. A Nigerian person gets a capitalized identifier unique to them. So does a Jamaican person. But what about the descendants of slaves here? They're American, of course, more specifically African American. But that's a mouthful, and they don't really have much connection to Africa except a genetic one. Their unique culture is something they created here out of a lot of totally separate parts of African culture, along with English culture. I think that all deserves a capitalized identifier that's unique to them.

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