Sino-American Cooperative Organization

The Sino-American Special Technical Cooperative Organization (Chinese:中美特种技术合作所), also known as the Sino-American Cooperative Organization (SACO), was an organization created by the SACO Treaty signed by the Republic of China and the United States of America in 1942 during the Second World War. It established a mutual intelligence gathering entity in China between the respective nations against Japan. It operated in China jointly along with the Office of Strategic Services (OSS), America's first intelligence agency and forerunner of the CIA while also serving as joint training program between the two nations.

The first and last operational chief of the organization was Dai Li (Tai Li, Dai/Tai is the surname), head of Chiang Kai-shek's secret police, the Bureau of Investigation and Statistics. A fierce anti-communist and shadowy man of mystery, General Dai also commanded the Loyal Patriotic Army (LPA), a large militia force active in Japanese-occupied interior regions of China. Commander for the American forces was United States Navy Captain Milton E. Miles. "Mary" Miles, later a Vice Admiral, was commander of Naval Group China (NGC), the American Navy's intelligence unit in China during the war.

In April 1943, SACO began setting up camps (later known as units when Naval Group China was established) to train Chinese guerrillas in small arms, demolition, sabotage, combat techniques, radio handling, aircraft and ship recognition, and aerology. Many, if not most, of the American instructors had backgrounds in law enforcement prior to the war. While some of the recruits the Chinese provided were unhealthy to some degree, they surprised their instructors with their willingness and ability to learn.

About 2500 sailors and Marines trained and operated with Chinese guerilla forces, often behind Japanese lines. Among all the wartime missions that Americans set up in China, SACO was the only one that adopted a policy of "total immersion" with the Chinese. The "Rice Paddy Navy" or "What-the-Hell Gang" operated in the China-Burma-India theater, advising and training, forecasting weather and scouting landing areas for USN fleet and Gen Claire Chennault’s 14th AF, rescuing downed American flyers, and intercepting Japanese radio traffic. An underlying mission objective during the last year of war was the development and preparation of the China coast for Allied penetration and occupation. The Foochow (Fujian Province) was scouted as a potential staging area and springboard for the future invasion of Japan.

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