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Mann, Thomas Clifton (1912–1999)

Mann, Thomas Clifton (1912–1999)

Thomas Clifton Mann, a career diplomat, was born 11 November 1912 near the border town of Laredo, Texas, and became bilingual at an early age. After working in the family law firm, he joined the State Department in 1942, specializing in Latin American affairs. He became a foreign service officer in 1947 and served as ambassador to El Salvador and as one of President Lyndon B. Johnson's principal advisers on Latin American policy. Mann advocated private, rather than public, investment and feared that Communists manipulated local nationalist movements in the Western Hemisphere. Therefore, he supported the Central Intelligence Agency's planned overthrow of Guatemala's Jacobo Arbenz Guzmán in 1954. Mann served as Assistant Secretary of State for Economic Affairs in the Eisenhower administration (1957–1960) when it shaped many of the policies subsequently found in the Alliance for Progress. After a stint as Ambassador to Mexico, Mann became Under Secretary of State for Economic Affairs in 1965. His advocacy of unilateral action by the United States in the Dominican Republic crisis of 1965 caused widespread criticism and contributed to his resignation in 1966. That same year President Johnson presented him with the President's Award for Distinguished Federal Civilian Service, and the Pan-American Society of New York awarded him its Gold Insignia. From 1967 to 1972 he was president of the Automobile Manufacturer's Association. In 1997 his alma mater, Baylor University in Waco, Texas, honored him as a Distinguished Alumnus. He died in Austin in 1999.

See alsoDominican Revolt (1965) .


Abraham F. Lowenthal, The Dominican Intervention (1972).

Stephen G. Rabe, Eisenhower and Latin America: The Foreign Policy of Anticommunism (1988).

Federico Gil, "The Kennedy-Johnson Years," in United States Policy in Latin America: A Quarter Century of Crisis and Challenge, 1961–1986, edited by John D. Martz (1988).

Additional Bibliography

Grandin, Greg. Empire's Workshop: Latin America, the United States, and the Rise of the New Imperialism. New York: Metropolitan Books, 2006.

Raymont, Henry. Troubled Neighbors: The Story of U.S.-Latin American Relations, from FDR to the Present. Cambridge, MA: The Century Foundation, 2005.

Sweig, Julia E. Friendly Fire: Losing Friends and Making Enemies in the Anti-American Century. New York: Public Affairs, 2006.

                                      Thomas M. Leonard

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