The Nixon Doctrine was a foreign policy strategy articulated by U.S. President Richard Nixon in 1969. It emphasized that the United States would support its allies in defending themselves, but would not commit American troops to conflicts unless vital national interests were at stake. This approach aimed to reduce U.S. military involvement abroad, particularly in Vietnam. Under the Nixon Doctrine, the U.S. encouraged its allies to take more responsibility for their own defense, promoting the idea of "Vietnamization." This meant that local forces would be trained and equipped to handle their security needs, allowing the U.S. to gradually withdraw its military presence from conflict zones.