U.S. President Richard Nixon outlined the Nixon Doctrine on July 25, 1969 during a press conference in Guam. The doctrine called on Asian allies of the United States to provide the bulk of the manpower for their own defense while still providing for American economic and military aid. The country most directly affected was Vietnam, but the doctrine indirectly impacted many nations around the world.

Effect on Vietnam

The Nixon Doctrine called for what President Nixon referred to as the "Vietnamization" of the Vietnam War. The U.S. would continue to lend air and artillery support to the war effort, but would expect the South Vietnamese to gradually take responsibility for the ground war. By 1972, Nixon had reduced American ground forces in Vietnam to one-third that of 1969 and by 1973, he called for the removal of all U.S. forces. This was a major factor in North Vietnam's 1975 victory in the war and in the 1976 establishment of the Socialist Republic of Vietnam.

Effects on Other Countries

Other American allies in Asia were affected as the United States reduced its troops at U.S. military installations, particularly those near China. Countries such as Japan and South Korea were expected to take on responsibility for their own national defense. Nixon's focus on moving from confrontation to dialogue with communist world powers led to improved relations with communist China -- and ultimately to improved relations with the Soviet Union and Soviet Bloc countries. Additionally, the Nixon Doctrine affected later U.S. foreign policy, such as the Reagan Doctrine, in which the U.S. supported foreign armies -- particularly in Latin America -- that were fighting communism rather than sending direct military intervention.