White people stiffen when blacks get on elevators,as you say, because they know blacks have low intelligence,on average, and fill US prisons and prisons around the world because of violent,impulsive actions.Supermarkets are non existent in black neighborhoods because of massive theft that makes doing business there impossible.This is a fact of nature.When well meaning peoples sang We are the World almost 25 years ago they did nothing because they could not change the fact that black Africa was inhabited by Black Africans.The intelligence level required to raise a modern society is simply not there on average.In future years this will only be compounded.No SANE white person would live in a black neighborhood in USA,Brazil,Europe etc.Those whites that are infected with Political Correctness and do try to live in these black neighborhoods are soon murdered by the blacks themselves.Again this is nature correcting itself.