Baby Boom The population increase which resulted from the high birthrate between 1946 and 1964. This generation created a strain on hospitals as it was born, in schools and colleges as it received its education, a glut in potential employees in the 1960s and 1970s, and, currently, threatens the Social Security and Medicare systems. Truman Doctrine The American policy, developed in 1947 in response to conditions in Greece and Turkey, which promised U.S. support to people resisting armed subjugation. The Truman Doctrine marks the shift in U.S. policy from isolationism to international cooperation and leadership. It had an ideological tone, committing theU.S. to resist communism everywhere, effectively making the U.S. into a national security state with a permanent military and more power vested in the President. Tet Offensive The North Vietnamese offensive of 1968 which showed that U.S. reports of imminent victory were misleading. Although the Tet Offensive resulted in a military defeat for the North Vietnamese, it was a strategic and political victory for North Vietnam because it discredited Washington's argument that U.S. victory inevitable and imminent, undermined U.S. morale, and it increased opposition to the war in the U.S. Johnson refused to grant requests for more troops and, on March 31, Johnson announced he would not seek re-election. Reducing U.S. involvement became a near necessity politically, affecting Nixon's policiesNSC (National Security Council) National security council paper drafted by paul Nitze and delivered to Truman in 1950 which provided a black and white view on future U.S. cold war policy. OPEC (Organization Of Petroleum Exploring Countries) An association formed by oil producing nations from the third would in 1960 to gain a voice for themselves in setting prices and production quotes for petroleum.