The belief that blacks, as a race, are superior to other races. Similar to Afrocentrism, but does not necessarily entail belief in ancient African achievements. To believe in black supremacy, one must not only be an expert in blame tactics, but be able to take blame to extremes that most ordinary humans are not capable of. After all, there is no evidence that blacks are a particularly accomplished race. In fact, evidence suggests they are the least accomplished of all races on earth. Thus, black supremacists must blame both bad luck and overwhelming racism as factors that "keep them down". Frequently, they also pretend that many common assertions about blacks simply aren't true (e.g. low IQ scores, black failure to create a prosperous government), requiring the asserter to go back to dig up some facts. By the time the asserter returns, the black supremacist is gone, either physically or mentally (i.e. changes the topic and refuses to discuss your evidence). To be a good black supremacist, one must be very good in the art of bullshit.
Black supremacists like Louis Farrakhan assert that blacks are kept down by other races, but one day the black alien mothership, which is orbiting Earth as we speak, will begin dropping bombs on all of the evil whites who keep them down.