The OSS undertook a wide variety of activities. In the United States, Donovan recruited academics for research and analysis functions. The OSS also mounted numerous covert activities, operating in both the European and Pacific war theaters. Ultimately, the OSS employed several thousand personnel. It had particularly close links with British intelligence services, which Donovan regarded as providing a desirable model for a potential U.S. agency. OSS European operations were based in London and headed by Colonel David K. E. Bruce, who subsequently became U.S. ambassador to France, West Germany, and Britain. OSS operatives (one of the more flamboyant ones was Allen W. Dulles, who spent the war in Switzerland cultivating contacts in Germany and Italy) infiltrated Axis-occupied territory, aiding resistance groups and providing the U.S. military with firsthand intelligence. In the Asian Theater, OSS agents worked closely with nationalist forces in China and Indochina, and as the war drew to a close they reported favorably though unavailingly to Washington on both the Chinese Communist movement led by Mao Zedong (Mao Tse-tung) and its Vietnamese counterpart headed by Ho Chi Minh.
Despite its successes, the OSS attracted fierce criticism from the American military, particularly General Douglas MacArthur, commander of U.S. forces in the southwest Pacific; military espionage operatives; and other rival intelligence agencies, such as the Federal Bureau of Investigation. Donovan's forthright style did little to allay such tensions. The OSS recruited its operatives disproportionately from the American social elite to which Donovan belonged, winning it the nickname "Oh So Social" and enabling detractors to denigrate its accomplishments. Immediately after the war ended, in September 1945 President Harry S Truman disbanded the OSS, ignoring Donovan's forceful pleas to establish a centralized U.S. intelligence agency. Within a few months, however, rising Cold War tensions led Truman to reverse this decision. The OSS was the de facto precursor of the Central Intelligence Agency, established by presidential executive order in 1946 and, more formally, by act of Congress in 1947. Many CIA operatives, including several influential directors—among them Allen W. Dulles, Richard Helms, and William Colby—began their intelligence careers as OSS agents. The CIA's subsequent heavy reliance on covert operations was another legacy that can be traced directly to its World War II OSS heritage. Priscilla Roberts
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