SAN FRANCISCO — The Beijing Olympics, once touted as a catalyst for openness and change in China, could wind up setting back the struggle for democracy and freedom in the world’s most populous country, according to the editor of a new book about the impact of the games on human rights there.

“The big open question is now, ‘Will the Olympics radically worsen the environment and will China go into a deep chill for a period, not unlike Tiananmen Square … or once the Olympics are out of the way can there be concrete, lasting reforms?'” the media director of Human Rights Watch, Minky Worden, asked yesterday during a global tour to promote the new volume, “China’s Great Leap: The Beijing Games and Olympian Human Rights Challenges.”

Ms. Worden said the potential for backsliding has grown in recent weeks as Chinese officials fueled nationalistic sentiment to counter the large and heated protests against the Olympic torch relay in Paris, London, San Francisco, and Seoul.

“The Olympics are all about nationalism, at one level. It’s about being proud of your team and your country, but I don’t think we’ve ever seen anything like this,” she said, referring to pro-China, anti-Tibetan messages in the state-run Chinese press. “After weeks now of anti-Tibetan propaganda throughout the newspapers and no coverage for many years of legitimate Tibetan concerns about religious autonomy, if I were a Chinese person living in China, I would not be aware of what the true situation is in Tibet.”

The nationalist fervor has the potential to lead to mob violence against a variety of protesters who will seek to publicize their causes during the Olympics, set to open August 8. “It’s a very difficult genie to stuff back in the bottle once you’ve let it out,” she said.

However, Ms. Worden, who speaks Cantonese and is a former adviser to a prominent Hong Kong democracy activist, Martin Lee, said recent history has shown that spasms of nationalism in China and the disorder that often follows are seized upon by hard-liners to fend off change. She cited “a pullback and a chill” after students angry about America’s accidental bombing of the Chinese Embassy in Belgrade rioted at the American Embassy in Beijing.

Another question the book highlights is whether six decades of repressive rule has left China unable to simply switch off its police-state tactics during the upcoming Olympics, even if the country’s leaders seek to do so.

The new volume’s introduction, penned by Nicholas Kristof of the New York Times, includes a chilling story suggesting that restraint may not be easily accomplished. Mr. Kristof reports that in 1993, when China was mounting its first, ultimately unsuccessful, bid to host the Olympics, a Communist Party neighborhood committee charged with beautifying its section of southern Beijing had a mentally retarded man, Wang Chaoru, 41, arrested without charge to avoid the possibility that visiting Olympic delegates might set eyes on him. Chaoru, who resisted, was reportedly beaten to death in police custody.

Plainly, no senior Chinese official ordered Chaoru’s arrest or his killing, but it was a direct and perhaps inevitable result of the zeal to please the “center” in a society with little respect for individual rights and no reliable check on police power.

One of the most counterintuitive chapters comes from an epidemiologist who studied China’s response to the outbreak of SARS in 2003, Joseph Amon. Before that crisis, many public health experts in the West quietly envied the quarantine and even the information-control powers of police states. Mr. Amon argues that the cover-ups that slowed the response to SARS and the AIDS crisis show that the most powerful prescriptions to fight disease there involve freeing the press and reining in pervasive corruption.

“That’s not the accepted cure for a pandemic,” Ms. Worden observed.

Given the prominence the Tibetan cause has taken in the recent torch protests, the book seems a bit light on discussion of that fight, as well as the restive Muslims in Xinjiang. Ms. Worden said her group has already put out voluminous reports on those subjects. “These are complex ethnic situations that don’t lend themselves to an easy chapter in a book,” she said.

Some of the few sour notes in the compendium come when a left-leaning sportswriter, Dave Zirin, mars an otherwise sensible argument about the deleterious local economic impact of most Olympics by including a tribute to antiwar protesters in London and a strange aside about the New York Police Department fighting a class war against the city’s poor.

Overall, the book paints a grim picture of human rights in China, but not one entirely without hope. A New York University professor, Jerome Cohen, chronicles a series of legal reforms China has passed but often ignores. Several contributors note that China has relaxed its rules for foreign correspondents, ostensibly eliminating a previous requirement that reporting in most of China be cleared in advance with provincial officials. However, the old rules are set to return after the games.

Ms. Worden pointed out that China’s promises of unfettered press freedom for the Olympics contain a huge caveat: They do not apply to Chinese journalists, who could serve as a kind of stopgap protection until political reforms arrive.

“If you could, through press freedom, surface more of the lead paint scandals or the corruption scandals, that’s actually going to benefit the country. They’ll sort out who the most corrupt cadres are,” she said. “If you’re not going to remove them through a democratic process, at least you will remove them by exposing them.”