American or not - choose one

I'm sick & tired of people claiming to be African American, Mexican American or Anything else American. You get one choice & if it isn't American, Leave because we don't want you here. All of us came from somewhere & although we can be proud of our heritage, we are here because we choose to be. Africans are the ones that sold other Africans into slavery but nobody seems to hate Africa for promoting slavery. Why not?