How mean are American high schools?

Check out this striking passage from an article in the current issue of The New Yorker (not online) -- the social culture in suburban high schools is so brutal that Somali refugees think they're awful places:

Fatuma Hussein cast a kind of sidelong light on this issue when she described the shock that she felt on arriving in America. Having escaped the horrors of the civil war and spent years in a refugee camp in Kenya, she was resettled, first, in suburban Atlanta, where she was sent to an all-white high school. "And I tell you," she said, "American high school is the cruellest place I've been."