Why don't people understand this about who is 'African American'?

How did a non-black get to be such an "expert" on blacks? Not all blacks accepts the term "African-American" as it's own ethnicity. So there. I'm an American who just happens to be black. All that other stuff is just foolishness. If they can do a DNA test on a black celebrity and get the location or tribe he/she is most likely affiliated, then I will save my money and find out exactly which people in Africa I belong to, but for now, I'm a black American. African-American always has been a cheesy @ss term in my opinion. I know most don't agree, and frankly I don't care;-)