ism's aren't genetic, they're taught.
Who is this person?
Despite the fact that "Kenyan daddy" kicked both Obama and his mother in the face by abandoning them, "Junior" modelled himself after his genetic father. He deliberately CHOSE his "-isms" to be the same as his maternal genetic material donor. "Junior" said so himself, repeatedly, in his writings. And an anti-British sentiment would "fit right in thtere" with his self-selected philosophical positions.
So, "self-taught" applies.