The United States has achieved a rare human rights breakthrough with China by negotiating the departure of dissident Chen Guangcheng, but few are ready to predict that the case will set a precedent.

The dramatic case has revived debate over what influence the United States holds on human rights with China's increasingly confident leadership, which in recent years has ended a practice of freeing dissidents as goodwill gestures.

Chen, a self-taught lawyer subjected to years of jail and house arrest for exposing forced abortions and sterilizations, arrived in New York Saturday, capping weeks of crisis between the world's two largest economies.

The 40-year-old last month pulled off an escape worthy of Hollywood. Despite being blind, he scaled walls in the dead of night as a getaway car took him from eastern Shandong province to the safety of the US embassy in Beijing.

Hours after Secretary of State Hillary Clinton arrived for previously scheduled talks, US officials escorted Chen to a hospital and said China had assured that he would be allowed to join his family and study in a safe place.

Some US administration officials privately believed they had reached a historic achievement that could serve as a template for future rights cases as Beijing had negotiated over the conditions of a citizen on Chinese soil.

But a number of US activists and lawmakers strongly criticized the initial deal on Chen, questioning why the Barack Obama administration would take China at its word. Within a day, Chen said that he was afraid for his family's safety and wanted to leave to the United States.

China, while quietly arranging Chen's departure, called for a US apology. The US State Department has been fastidious over its public language on Chen and repeatedly called the case "extraordinary."

Bonnie Glaser, a senior fellow at the Center for Strategic and International Studies, doubted that Chen's case would start a trend. She pointed to exceptional factors -- Chen is blind and had broken bones when he sought US help, while China was eager to ensure smooth talks with Clinton.

China's leadership -- keen to avoid instability, particularly as it undergoes a once-in-a-decade political transition -- is acutely aware that many dissidents lose influence once they leave, Glaser said.

"Frankly, I think that a deal that got him out of the country was the best thing for China's leadership," she said.

China had a sharply different reaction when another dissident, Liu Xiaobo, won the Nobel Peace Prize in 2010. Liu remains in prison and China has sought to punish Norway, the host of the award.

But Sophie Richardson of Human Rights Watch said that -- even if it is unlikely that droves of dissidents will seek shelter at the US embassy -- the Chen case showed activists inside China the possibilities of pushing the government.

"I have trouble imagining that people who will have watched this saga unfold won't in some ways feel empowered by it," she said.

Obama administration officials, heading into an election in November, have cast Chen's departure as the culmination of a long effort to build a working relationship with China, often behind closed doors.

Sharon Hom, executive director of Hong Kong- and New York-based group Human Rights in China, said the Chen case did not give simple answers on whether quiet or loud diplomacy works best with China as many factors -- from international attention to Chinese netizen activism -- had been factors.

Hom said that Chen's situation broke new ground as he was able to achieve his wish of studying at New York University accompanied by his family and -- officially at least -- has the right to return to China.

Usually, dissidents face the stark choice of abandoning their families or staying in China under threat.

But Hom said it was too early to assess the impact. Chen has charged that provincial authorities are now going after his nephew, slapping a murder charge against him of what Chen said was self-defense against thugs.

"Chen's stay in the US to rest and study, while an important next step for him and his family, does not resolve his future, guarantee the safety of his family, supporters and other activists back in China, or address the serious corruption and human rights abuses exposed by Chen and other activists," Hom said.