It is always good to have someone in the "reserve" who threatens order and freedom in America. So I guess attention is diverted from what whites in power do. These who threat could be communists in America itself or once in the form of the Soviet Union, as well as many external and internal "enemies". This is the easiest way to maintain an order that suits the powerful. These "enemies" can be the citizens of America themselves, depending on what is easiest to apply at a given moment. Yet if minorities clash with each other, even better. This could be one of the explanation for the source of systemic racism in the American system from the beginning.