DURHAM, N.C.  On the day the Olympic torch was carried through San Francisco last week, Grace Wang, a Chinese freshman at Duke University, came out of her dining hall to find a handful of students gathered for a pro-Tibet vigil facing off with a much larger pro-China counterdemonstration.

Ms. Wang, who had friends on both sides, tried to get the two groups to talk, participants said. She began traversing what she called “the middle ground,” asking the groups’ leaders to meet and making bargains. She said she agreed to write “Free Tibet, Save Tibet” on one student’s back only if he would speak with pro-Chinese demonstrators. She pleaded and lectured. In one photo, she is walking toward a phalanx of Chinese flags and banners, her arms overhead in a “timeout” T.

But the would-be referee went unheeded. With Chinese anger stoked by disruption of the Olympic torch relays and criticism of government policy toward Tibet, what was once a favorite campus cause  the Dalai Lama’s people  had become a dangerous flash point, as Ms. Wang was soon to find out.

The next day, a photo appeared on an Internet forum for Chinese students with a photo of Ms. Wang and the words “traitor to your country” emblazoned in Chinese across her forehead. Ms. Wang’s Chinese name, identification number and contact information were posted, along with directions to her parents’ apartment in Qingdao, a Chinese port city.