<P> During the Malayan Emergency (1948--1960), Britain was the first nation to employ the use of herbicides and defoliants to destroy bushes, trees, and vegetation to deprive insurgents of concealment and targeting food crops as part of a starvation campaign in the early 1950s . A detailed account of how the British experimented with the spraying of herbicides was written by two scientists, E.K. Woodford of Agricultural Research Council's Unit of Experimental Agronomy and H.G.H. Kearns of the University of Bristol . </P> <P> After the Malayan conflict ended in 1960, the U.S. considered the British precedent in deciding that the use of defoliants was a legal tactic of warfare . Secretary of State Dean Rusk advised President John F. Kennedy that the British had established a precedent for warfare with herbicides in Malaya . </P> <P> In mid-1961, President Ngo Dinh Diem of South Vietnam asked the United States to conduct aerial herbicide spraying in his country . In August of that year, the Republic of Vietnam Air Force conducted herbicide operations with American help . But Diem's request launched a policy debate in the White House and the State and Defense Departments . However, U.S. officials considered using it, pointing out that the British had already used herbicides and defoliants during the Malayan Emergency in the 1950s . In November 1961, President John F. Kennedy authorized the start of Operation Ranch Hand, the codename for the U.S. Air Force's herbicide program in Vietnam . </P> <P> During the Vietnam War, between 1962 and 1971, the United States military sprayed nearly 20,000,000 U.S. gallons (76,000 m) of various chemicals--the "rainbow herbicides" and defoliants--in Vietnam, eastern Laos, and parts of Cambodia as part of the aerial defoliation program known as Operation Ranch Hand, reaching its peak from 1967 to 1969 . For comparison purposes, an olympic size pool holds approximately 660,000 U.S. gal (2,500 m). As the British did in Malaya, the goal of the US was to defoliate rural / forested land, depriving guerrillas of food and concealment and clearing sensitive areas such as around base perimeters . The program was also a part of a general policy of forced draft urbanization, which aimed to destroy the ability of peasants to support themselves in the countryside, forcing them to flee to the U.S. - dominated cities, depriving the guerrillas of their rural support base . </P>

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