TOKYO — As Japan's defeat marking the end of WWII nears its 80th anniversary, and some events fade from living memory, history is hardly consigned to books. It lives on in unhealed wounds, still-simmering disputes, freshly unearthed discoveries, and historical lessons waiting to be learned.
The release of WWII-era military documents this year has given a boost to researchers digging into Japan's notorious germ warfare program, which lasted from 1936 to 1945. And in China, the premiere of a film about this gruesome episode in history was postponed without explanation, causing an online outcry.
Titled 731 Biochemical Revelations in English, the film tells the story of Chinese victims of the Japanese Imperial Army Unit 731's inhumane medical experiments.
When the screening was canceled and later pushed back to September without explanation, some film fans questioned the authorities' motives, wondering whether the move was intended to avoid a spat that could damage fragile ties between Beijing and Tokyo.
"Just because the movie exposes scars, does that mean people should choose to forget that part of history?" asked state-run Hunan Satellite TV anchor Liu Jiaying in a social media video. "This film is not only a retelling of the past but also a warning to the future," she added.
First-hand accounts are rare
One of the last eyewitnesses able and willing to speak about Unit 731 is 95 year-old Hideo Shimizu, who lives in central Japan's Nagano prefecture.
He joined Unit 731's Youth Corps at age 14 and arrived at unit headquarters in Japanese-occupied Northeast China in 1945, five months before the end of the war.
In an interview at his home, he says he assumed he would be given some manufacturing job, so he was surprised to see doctors in white lab coats at the headquarters.
He says he never imagined he would be doing anything related to medicine, much less working in a unit accused of dissecting live prisoners, some without anesthesia, infecting them with diseases or conducting germ warfare against Chinese soldiers and civilians.
Shimizu remembers that the first inkling he got that something terrible was happening was when he was led one day into a room filled with specimens of human organs in glass jars.
"The most shocking thing for me," he recalls, "was a specimen of a whole female body with a fetus in its womb."
Shimizu says he himself became seriously ill, after an older unit member gave him a piece of bread, and he believes that the unit carried out experiments on its own youth corps trainees.
As Japan's defeat loomed, unit 731 members were instructed to destroy evidence — and witnesses. Unit 731 doctors called the people they experimented on "maruta," or logs, in other words, not human.
"I did not see any of the maruta alive," Shimizu says. "All I did was collect their bones and put them in a bag," after they had been killed and their bodies burned.
Unit 731 is estimated to have killed around 3,000 people, while bioweapons developed by other branches of the program are believed to have killed far more.
Japan's government has never apologized for Unit 731's actions, and insists that it has found no evidence that the unit experimented on Chinese prisoners, even though a Tokyo court ruled in 2002 that the military had conducted such experiments and waged biological warfare.
Last year, Shimizu traveled to China to apologize. He has faced criticism in Japan for speaking out. Others, like Hideaki Hara, a former school teacher who has curated part of an exhibit dealing with Unit 731 at a local museum in Nagano, support him.
"When we talk about the war, it's easier to talk about ourselves as victims, such as of the atomic bombings," Hara says. "But our role as perpetrators is not often discussed. People don't want to talk about it."
Uncovering a secret history
But 77-year old Katsutoshi Takegami wants to talk. Several years ago, in his home in Nagano prefecture, he discovered a trunk that belonged to his father.
It contained photos that showed his father serving in Unit 1644, another part of Japan's biowarfare program. Since then, Takegami has been researching his father's military service.
"If you kill a lot of people, you become a hero and get promoted," he says. "I was worried that my father had done something bad, and that's how I got started investigating this thing."
In May, at the request of researchers, Japan's national archives made public Unit 1644's personnel rosters. Takegami hopes to use the rosters to track down any surviving members of the unit.
"I feel the personnel rosters are a treasure," says Lv Jing, a historian at Nanjing University, in the city where Unit 1644 was based. She believes the rosters will enable researchers to better understand the structure of Japan's germ warfare system.
Researchers in recent years have discovered a network of units, stretching from Unit 731 in the north to Unit 8604 in southern China's Guangzhou city, and down to Unit 9420 in Singapore.
Lv says that each unit "tried to adapt to local conditions, solving problems in the environment they were fighting in, and using them against their enemy."
With euphemistic names such as "anti-epidemic and water supply" units, their job was to keep their own troops healthy, while getting their enemies sick, by spreading diseases such as plague and malaria.
After the war, an international tribunal, known as the Tokyo Trial — similar to the Nuremburg trials in Germany — sentenced seven Japanese officials to death for war crimes.
But Lv Jing notes that Unit 731's leaders returned to Japan, where many of them led illustrious careers as heads of medical institutions and pharmaceutical companies.
That's because the U.S. gave Unit 731 leaders immunity from prosecution, and withheld evidence of their war crimes from the tribunal, in exchange for the data from the unit's medical experiments. The U.S. government kept the details of Unit 731 and its immunity deal secret for decades.
"It is a lapse of justice to the highest degree," says Cambridge University professor of East Asian History Barak Kushner. "And of course, the reason it's kept out mainly is Americans want the data for themselves and they don't want the Soviets to get it."
Similarly, Kushner notes, the U.S. gave German scientists, including former Nazi party members, immunity in exchange for their help with U.S. missile and space programs, a program known as "Operation Paperclip."
In Japan, the U.S.' overriding concern was to rebuild the country, Kushner says, into a bulwark against communism.
"I think the immunity offered in that situation reflects the tenor of the times, the political situation, and perhaps the limits of what sort of justice was achievable" for war crimes in the immediate post-war era, Kushner says.
It was one important episode, he adds, in which American ideals of justice took a back seat to self-interest and national security.
Chie Kobayashi contributed to this report in Nagano Prefecture and Tokyo
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