You see, that's the problem I have with USA culture: why would word "black" be an offensive word? What should I describe my black classmate's race in University? African-British? What if they're not British? Should I asking their nationality every time I meet new friend who is black?
If word "black" is indeed racially insensitive and offensive, then I shall declare that the word "yellow" is too, racially insensitive and offensive, because I'm an Asian, and my skin colour is yellow.
I wouldn't even tell you that during my time in secondary school, I insist my Muslim friends to call me "Chigga", since the N-word is such an forbidden word.