Unit 731

Unit 731 was the name given to a secret chemical and biological weapons program that was run by the Japanese Army in China from 1936 to 1945. Unit 731 was infamous for its extreme methods and excessive cruelty. Its doctors experimented on human subjects, often in horrific and sadistic ways. They performed surgery on victims without anesthesia, removed limbs, exposed people to extreme temperatures, and purposely infected subjects with deadly diseases. Several thousand people are estimated to have died as a direct result of the unit's experiments; many tens of thousands more are believed to have been killed in field experiments on local populations. Upon Japan's surrender at the end of World War II (1939–1945), many of the unit's doctors were granted immunity from war crimes in exchange for the scientific data they collected.

Background

While armies had been attempting to use crude forms of biological and chemical warfare against each other for centuries, it was during World War I (1914–1918) that this form of warfare was first used to devastating effect. Spurred by scientific advances, both the Germans and Allied forces employed chemical weapons such as cyanide gas, chlorine gas, and sulfur-based mustard gas during battle, killing an estimated one million troops on both sides. The effect of the weapons was so horrific that the world's leading powers agreed in 1925 to ban their use in future conflicts.

Japan had fought in World War I on the side of the European and American Allies. The island nation had long sought to become a great world power and had begun to model its foreign policy after the European strategy of acquiring colonial holdings. The most logical target for Japanese expansion was China, which at the time was a politically divided nation with vast natural resources. By 1915, Japan had gained control over much of China's railway system and annexed the Korean Empire.

In the early 1930s, Japan's economy was suffering and China's warring political factions had begun to unify. Fearful of losing its control over its Chinese interests, Japan invaded Manchuria, a region in northeastern China. By 1937, Japan and China were engaged in a full-scale war. The Japanese felt that they were superior to the Chinese and often employed brutal tactics during the war, massacring large numbers of civilians and soldiers.

Overview

Japanese military officials had become interested in chemical and biological weapons after the international community banned them in 1925. They reasoned that if the world's great military powers were so concerned about their use in warfare, they must make powerful weapons. Japan established its first biological weapons program in 1932 under the command of microbiologist Shiro Ishii. In 1936, Ishii was placed in charge of a larger program at a newly built facility in the Pingfan district outside of Harbin, the largest city in Manchuria. The program operated under extreme secrecy and was officially called the Epidemic Prevention and Water Supply Unit of the Kwantung Army. It was not called Unit 731 until 1941. The program had a staff of several thousand and was housed in 150 buildings equipped with laboratories, operating rooms, military barracks, and several cremation facilities.

The Unit 731 facilities were separated into eight divisions. Division 1 was responsible for bacteriological research, such as the study of bubonic plague, typhoid, anthrax, and cholera. Division 2 was responsible for researching ways to use biological warfare in the field by discovering ways to spread disease upon a battlefield. The remaining six divisions were either administrative, tasked with clinical diagnosis, or responsible for producing and storing bacteriological agents.

The researchers at Unit 731 used human subjects for their experiments, drawing their victims from political prisoners, criminals, the poor, and homeless. Their victims also included women and children. The test subjects were mostly Chinese and Russian, but it is rumored that captured British and American soldiers were also used in the experiments. The doctors referred to the subjects as maruta, or "logs," comparing their deaths to the cutting down of trees.

Researchers performed surgeries and vivisections on their victims without the use of anesthesia, removing organs and severing limbs; the rationale behind such cruel methods was the belief that a live, unanesthetized test subject provided more useful results. Some victims had their limbs amputated and reattached to other parts of their body; others were subjected to extreme cold to gauge the effects of frostbite and gangrene on human skin. Many were exposed to poison gas or deadly diseases to observe the amount of time it took a person to show the effects or symptoms before dying.

Among the most disturbing experiments carried out by Unit 731, doctors subjected victims to starvation, dehydration, extreme air pressure, or electrical current to see how long a human could survive under such conditions. Researchers also exposed nearby cities and villages to deadly diseases by dropping bubonic plague–infested fleas on an unsuspecting population, or poisoning wells with cholera and typhoid. At least three thousand people are believed to have been killed directly in Unit 731's laboratory and medical experiments; estimates ranging from thirty thousand to more than five hundred thousand are believed to have died in field tests of diseases on the Chinese population.

After a 1942 field test accidentally infected more than one thousand Japanese soldiers with cholera, Unit 731 began to concentrate on ways to equip bombs and artillery shells with deadly diseases. One method they developed would disperse a cargo of plague-infested fleas upon detonation. The Japanese were planning to use these weapons against the United States, either by attaching them to balloons and setting them adrift across the Pacific or dropping plague bombs by aircraft on US cities.

Upon Japan's surrender in August 1945, most of the staff of Unit 731 returned home to Japan. Several of those who remained behind were captured by the Soviet Union and sentenced to prison for war crimes. The US Army investigated the actions of Unit 731, but instead of prosecuting its members, the United States offered its officers immunity in exchange for the scientific data they had complied. Shiro Ishii was never tried for his crimes and died of cancer in 1959. Other members of Unit 731 went on to become high-ranking officials in the Japanese government and the medical profession.

Aided by the American cover-up, the Japanese government long denied the existence of Unit 731. It was not until the 1980s that Japan admitted it had conducted human biological warfare experiments. In 2002, a Japanese district court ruled for the first time that Japan had engaged in biological warfare. In 2018, the National Archives of Japan released the names of 3,607 members of Unit 731.

Bibliography

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Ryall, Julian. "Human Bones Could Reveal Truth of Japan's 'Unit 731' Experiments." Telegraph, 15 Feb. 2010, www.telegraph.co.uk/news/worldnews/asia/japan/7236099/Human-bones-could-reveal-truth-of-Japans-Unit-731-experiments.html. Accessed 22 Nov. 2024.