I think so too.
And that isn't to say that it's anyone fault, or that anyone is inferior or superior to anyone else, which is what some people hear when it is pointed out.
I think all ethnicities/groups are guilty of it to some degree. For example, many North American or European people live in "ex-pat" villages within foreign cities.
Cultures are separated geographically for a reason. In some cases, cultures are so different and incompatible with others, that they have to be kept at a distance. When we forcefully and systematically squish people into large multicultural cities, the normal culture of that place breaks down. A broken culture is a weakened culture. I feel there are agendas at work, with something to gain with this divide and conquer tactic.
I recently asked "What if a group of people tried to control society?" and I wonder if that has anything to do with it?