U.S. President Lyndon B. Johnson landed 42,000 troops in the Dominican Republic in 1965 to prevent the emergence of "another Fidel Castro." More notable in 1965, however, was U.S. intervention in Southeast Asia. In 1965 Johnson stationed 22,000 troops in South Vietnam to prop up the faltering anticommunist regime. The South Vietnamese government had long been allied with the United States. The North Vietnamese under Ho Chi Minh were backed by the Soviet Union and China. North Vietnam, in turn, supported the National Liberation Front, which drew its ranks from the South Vietnamese working class and peasantry. Seeking to contain Communist expansion, Johnson increased the number of troops to 575,000 in 1968.