In April 2007, the acting chief of the U.S. Embassy in Beijing met China's assistant foreign minister and discussed Iran, Nepal, and North Korea. He also raised the "apparent detention" of a blind lawyer named Chen Guangcheng.

At the time, China’s central government insisted Chen was free. According to a cable released by WikiLeaks, U.S. diplomat David S. Sedney disputed that assertion, and said: "not being able to trust clear statements by [foreign ministry] officials damages our ability to work with China."

Five years later, the United States is more deeply involved with Chen’s case than ever, with U.S. officials escorting him from the American Embassy to a Beijing hospital on Wednesday and securing assurances on his behalf. Chen found refuge for a week inside the embassy after fleeing de facto house arrest, and U.S. officials have made themselves responsible for guaranteeing his safety and holding Chinese authorities to their commitment to treat him “humanely.

All of which means that human rights again have been thrust to the top of the Sino-U.S. agenda, just as Secretary of State Hillary Rodham Clinton and Treasury Secretary Timothy F. Geithner arrive in Beijing for talks on a broad range of issues, from Iran, North Korea and Syria to ways the two sides can help revive global economic growth.

No matter what priority successive administrations give the rights issue, it has proven impossible to ignore — often at the most inopportune times. U.S. diplomats tend to prefer to make their human rights views known privately. But in cases like Chen’s, such discretion is simply impossible.

"The question has always been the place of human rights on the American agenda with China — how high up and tactically how is it pursued," said David Shambaugh, director of the China policy program at George Washington University. "It's never been a question of whether it is on or off the agenda."

Shortly after becoming secretary of state in 2009, Clinton drew criticism for a reply to a question about how she would approach China's human rights abuses. "We know what they are going to say because I've had those kinds of conversations for more than a decade with Chinese leaders," Clinton said. "We have to continue to press them. But our pressing on those issues can't interfere with the global economic crisis, the global climate change crisis and the security crisis."

Human rights groups said she was lowering the profile of human rights.

From the Chinese side, too, Chen’s saga shifts the spotlight away from mutual strategic and economic concerns, which had been where they wanted it. At a moment when Chinese officials would have preferred talking about the positive aspects of the U.S-China relationship, they found themselves again in the position of denouncing the U.S. for “interfering in China’s internal affairs” in the Chen case.

Still, Chinese officials seem to recognize — perhaps with more resignation than acceptance — that the human right issue is always a part of the broader relationship with the U.S., whether they like it or not. Rather than bristling at the mention of human rights problems, Chinese diplomats seem to have adopted a more nuanced response. They stress that no country, including the United States, has a perfect human rights record, and they try to seek recognition for the progress that has been made in China, even while acknowledging that problems remain.

“We do not refuse to discuss issues with the U.S. side that are of interest to the U.S. side,” Cui Tiankai, the vice minister for foreign affairs in charge of U.S. policy, acknowledged in a briefing last week. “But it must be done on the basis of mutual respect. We hope that such discussions can help our American friends have a more accurate understanding of the real situation.”

Vice President Xi Jinping, the country’s leader-in-waiting, used this approach during a U.S. trip earlier this year. Speaking to members of Congress, Xi used a line from a once-popular Chinese advertising jingle: “There is no best, only better.”

Cui picked up the same theme in his press briefing. “On the question of human rights,” Cui said, “ we hope the U.S. side will have a better understanding of the history of human rights in China, what progress we have made and what challenges we still face.”

“It’s quite inevitable for there to be individual cases of violations of human rights in both countries,” Cui said. “So we should look at the overall trend. . . . No one can say they have a perfect human rights situation. There is always room for improvement.”

Ever since the United States reestablished diplomatic relations with the People's Republic of China, human rights has been a thorn in the side of relations that are already full of other challenges. But U.S. presidents frequently try to put the conflict onto a back burner.

When President Richard Nixon first visited China, he turned a blind eye to the Cultural Revolution that was still in progress. In 1994, President Bill Clinton decided to "de-link" human rights and trade so that China could join the World Trade Organization, though the State Department later presented Beijing with a list of prisoners the U.S. thought should be freed.

Even when the United States pays attention to human rights, it must choose which human rights to highlight.

"During the [President George W.] Bush years, religious freedoms were the highest element of the human rights basket," Shambaugh said. But, he added, there are also ethnic rights, workers’ rights, child labor and workplace safety.

"Right now we've got this blind activist capturing everyone's attention, but Tibetans have been immolating themselves for months and there is a complete dragnet around Tibet," Shambaugh said.

Kenneth Lieberthal, a China expert at the Brookings Institution and former senior director for Asia at the National Security Council, said that criticism of Hillary Clinton for her compartmentalized approach was unduly harsh.

"She said we have four baskets of issues," he said. "All of them are tremendously important, and we cannot let one interfere with our ability to pursue the others."

Lieberthal cited the need to work with China to prevent Iran from getting nuclear weapons, stabilize North Korea and ensure that China's trade policies do not harm U.S. jobs and growth.

"The question has been, do you do [discuss rights abuses] publicly or behind closed doors," Shambaugh said. "The Chinese are sensitive because in their culture public criticism is public shaming, losing face. They prefer behind-closed-door approaches and those have, in the past produced results."

Behind-the-scenes outreach by John Kamm, who as a private businessman led his own personal quest to persuade Chinese officials to free political prisoners, often was successful. "So much depends, insofar as China is concerned, on what, at any particular time, are their own motivations for even considering human rights concessions," said Kamm, who now heads the Dui Hua Foundation.

After the Sept. 11, 2001, attacks on the United States, Kamm said, "the conventional wisdom was that the U.S. needed China more than China needed the United States, for the war on terror. . . .Under those circumstances getting concessions would be more difficult than ever.

“But as it turns out, the period after 9/11, insofar as prisoner releases is concerned, was the most productive period since . . . the early 1990s."

Richburg reported from Beijing.