No more than the Moors used their superiority to create a system to favor Africans when they conquered Spain. They had the power, which did not make them superior to white people.
Indeed, the fact that black people used their courage and ingenuity to throw off segregation in states were it was law, gives lie to the idea of white superiority. Doesn't mean that blacks are superior either; it merely means that segregationists aren't very bright people, and when faced with a novel way of fighting their oppression, they responded in ways that played into the hands of black people, being no match for the genius and courage of blacks seeking freedom.