Seventy years after Japanese troops killed tens of thousands – probably hundreds of thousands – of Chinese civilians and prisoners of war in a six-week orgy of violence here, Thursday's commemoration of their deaths illustrated how deeply woven the massacre still is into the fabric of Sino-Japanese relations.
Anxious to improve ties with Tokyo, the Chinese government sent only junior officials to a ceremony unveiling a refurbished museum documenting the event. None addressed the crowd of invited students, soldiers, and construction workers.
"There isn't nearly the attention seen in previous years" in the state-run press, says Russell Leigh Moses, an analyst in Beijing. "There seems to have been a deliberate effort to downplay" the anniversary "tied into the state of Sino-Japanese relations and hopes for their future."
But as leaders on both sides of the Yellow Sea seek rapprochement, conflicting memories of Imperial Japan's eight-year occupation of China are proving "the key problem in our relations," says Bu Ping, a historian who leads a team of Chinese and Japanese scholars seeking common ground.
"Historical events should not normally impact bilateral relations like this," adds Huang Dahui, the head of Asian Studies at Beijing's Renmin University. "But they do indeed have an influence."
The horrors of the occupation are laid out in ghastly detail at the Nanjing Massacre Compatriot Victims Memorial Museum, a granite building on the site of a mass grave, parts of which have been left, strewn with skeletons, as it was found.
Reopened Thursday after two years of renovation, the museum uses photographs – many taken by Japanese soldiers – archive film, and contemporary artifacts to detail the slaughter that the Chinese authorities say left 300,000 dead and 20,000 women raped.
Though arguments continue over the death toll, "how many died is not important; the nature of the massacre is the main point," says Zhang Xianwen, a history professor at Nanjing University who recently edited an eight-volume collection of the details of 13,000 victims.
Doubts persist in Chinese minds, Professor Zhang adds, that the Japanese authorities fully acknowledge that what Tokyo refers to as the "Nanjing Incident" was in fact "a large-scale massacre in which Japanese troops killed a lot of peaceful citizens and unarmed soldiers."
Some right-wing Japanese nationalists deny the Nanjing Massacre ever occurred. The Japanese government, meanwhile, has never formally taken responsibility for what the Chinese side says occurred.
"There are a lot of different views about what really happened" in Nanjing, Japanese Foreign Ministry spokesman Mitsuo Sakaba said recently.
Japan has issued a number of general apologies for its troops' wartime behavior, starting with its statement in 1972 normalizing relations with China that it was "keenly conscious of the responsibility for the serious damage that Japan caused in the past to the Chinese people through war, and deeply reproaches itself."
But that and subsequent declarations did not stop former Japanese Premier Junichiro Koizumi and other top officials from repeatedly visiting the Yasukuni shrine in Tokyo to pay homage to Japan's war dead, including condemned war criminals.
"If they keep visiting the shrine, apologies mean nothing," says Professor Huang. "Yasukuni is the symbol of the invasion. It is like rubbing salt in the wound."
Since Mr. Koizumi stepped down 15 months ago, his successors have avoided going to Yasukuni, paving the way for better relations with Beijing.
Then-Prime Minister Shinzo Abe visited China soon after taking office, and his Chinese counterpart, Wen Jiabao, returned the compliment last year. Current Prime Minister Yasuo Fukuda is due in Beijing next month, and Chinese President Hu Jintao is expected to go to Tokyo next April, the first presidential trip there for a decade.
Improving ties apparently dissuaded Beijing from making a major occasion of the anniversary, and from remonstrating publicly with Japan for alleged lack of contrition. "To remember the historical is to cherish the momentum of improvements so as to create a better future," Chinese Foreign Ministry spokesman Qin Gang said this week.
"If Japan does not push us, the [Chinese] government will mark the anniversary in a low-key mode," says Mr. Bu. "There is no need to mark it very loudly."
But the way Beijing ties current relations to how history is remembered strikes some historians here as dangerous. "It is not normal that when relations are good, the governments don't talk about history, but when they are bad, they play the history card," says Mr. Zhang. "History is history ... we should learn from it. Commemoration should be normalized, not affected by relations between the two countries."
That is the goal Bu is pursuing with his team of 20 Chinese and Japanese historians, who are debating more than a dozen tough issues that dog bilateral relations.
Bu says "they should reach agreement on the nature of the war and the evaluation of major wartime events" in a report to be published next June. So far, he says, they have found general agreement on "historical facts," but encountered difficulty in agreeing on interpretation.
The project is perfunctory, he says, compared with the work French and German scholars did before compiling a joint history of 20th-century Europe. "We still have a long way to go," he admits. "But at least we have made a start."