I have not done very much research into AA but my impression is that it was established to aid those that early America actively oppressed, thus stunting their growth as a productive part of the economy. I believe this encompasses those of Native American, Mexican and African descent. Be it Oppression, War or Slavery, these cultures were undeniably hurt by the American Government in one way or the other. From my understanding, while Asians were never shown the respect of equals in America, they were also never actively opposed by the government until the World Wars.

At least, that is how I've come to think of it. Forgive me if I show my ignorance.