[_delirium]

I've often found cliquishness when there's, say, five people, of which four are from the same age/sex/ethnic/cultural/etc. background, and the fifth is from something different. It's worse when the four are from a quite narrow background of similarity, like four guys of the same age/race/major/etc. from Stanford, or four immigrants from the same country.

[rdl]

If you put it that way I sort of agree, although I think Americanized ethnicity or race is much less dominant as a trait than other traits.