I don't think that other countries have had their social fabric broken down quite as far as Americans have. A big part of American fear is knowing that nearly every single person you interact with that isn't a friend of yours doesn't really consider you their "people". No matter what ethnicity or social class you come from, if you leave the house you're going to spend a lot of time around people that don't feel any particular loyalty to you, and you end up always watching your back. Can't trust the cops, can't trust the poor people, can't trust the rich people, don't know your neighbors that well, just keep your eyes on your phone.

(This isn't just a skin color thing, even white people in America have such diverse in-cultures that it feels bizarre to speak to some of them. Go down five houses in a richer white neighborhood and you will not typically find neighbors that share really common understanding among one another.)