by Danielle Dybbro
The systematic medical experimentation of Chinese, Korean, Mongolian, and Allied prisoners during World War II was conducted by the Japanese military with the operation’s headquarters based in Harbin, Manchuria. Unit 731, also known as the Epidemic Prevention and Water Supply Department, was responsible for the deaths of at least 3000 people in the Manchurian headquarters from 1939-1945 and the experimentation of at least another 250,000. Prisoners were victims of such procedures such as live vivisection, frostbite, and disease experiments, all in the name of furthering Japanese medical, military, and biological warfare research.
Historians estimate that at least half a million people were killed as a direct or indirect result of the biological warfare field tests throughout China, which included airplanes dropping ceramic bombs filled with plague-infested fleas, anthrax contaminating water supplies, and lacing food with other infectious diseases. This biological warfare research was even considered as a tool to attack the United States: the military plan codenamed Cherry Blossoms at Night was in the works, which would have involved kamikaze pilots infesting California with the plague.
Unit 731 was just one of many Epidemic Prevention Departments, with at least 5 other permanent facilities in China, Japan, and Singapore, and at least 18 others throughout the Japanese Empire. However, In August 1945, Japan surrendered to the Allies and Unit 731’s leader, General Shiro Ishii, ordered his more than 10,000 workers to bury the evidence by destroying the facilities, killing and burying the remaining prisoners, releasing all disease-infected animals, and taking their secrets to the grave.
The United States granted General Ishii and a number of other prominent Unit 731 workers immunity from war crime investigations in exchange for the medical research they accumulated from their experiments. The Soviet-U.S. rivalry was soon to turn into the Cold War, and the U.S. wanted to get ahead of the USSR in biological warfare research. The U.S. did not want the publicity of an international war crime trial, which would leak any of the secret and valuable research to the Soviets that the Japanese had accumulated at the high cost of hundreds of thousands of human lives. As a result of this war crime immunity, a number of Unit 731 officials were able to become prominent members of society, including professors at medical schools, the director of Japan’s largest pharmaceutical company, the president of Japan’s Medical Association, and the head of the Japanese Olympic Committee.
Former members of Unit 731, including medical assistants, nurses, and doctors, have come forward and admitted to following the orders to perform experiments on prisoners and to cover up the evidence at the end of the war. However, to this day, the Japanese government has not taken responsibility for the nearly 1 million deaths that Unit 731 and its biological warfare division is estimated to have caused. Neither have any lawsuits filed by Chinese families affected by Unit 731’s research been answered by the Japanese government.
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