Well, the terminology keeps changing. Years ago AAs were not so easily offended like today. Today you can’t even tell an ethnic joke without being tossed into prison...
I think the sequence was:
Colored folk
Negro
Black
African-American
At some point this will change again I believe.
Colored folk
Negro
Black
African-American
You, sir, are exactly right, though the first two terms were used interchangeably for 150 years. MLK made the term, 'negro', the more politically correct of the two, then the radicals who followed, abolished both terms, favoring the simple, 'black', as a racial identifier.
Later, Obama's generation of leftist academics created the abominable 'A-A' appellation. I think I first heard it in the late seventies, and considered it a pretentious mouthful.