"Safest countries in the world" is casting a pretty wide net. Yes, there are hundreds of countries worse. What is your point? Remove those worst countries and the US and it is pretty average compared to richer countries in the world.
And that's the thing, isn't it? America is mostly super-low crime, but for some reason we have a dysfunctional criminal underclass that just won't go away. Japan seems weird to us because theirs is smaller than ours (and often held in check by Yakuza higher-ups with calmer heads.) Why do US cities have so many neighborhoods where you Do Not Go, while almost all of the US has no neighborhoods where you feel even vaguely unsafe?