May 1, 1960 - CIA pilot Francis Gary Powers, flying a U-2 spy plane, was shot down over Russia on the eve of a US/Soviet summit meeting. The meeting was cancelled and intensified Cold War tensions. Powers survived the shootdown and convicted by a Soviet court. He was released two years later in exchange for a Soviet spy.
May 7, 1954 - The French fortress of Dien Bien Phu, fell to Vietnamese forces in northern Vietnam, effectively ending the French/Indochina War.
May 12, 1949 – The Berlin Blockade was lifted. The blockade began on June 24, 1948 and lasted for 462 days. - The Berlin airlift consisting of American and British aircraft delivering food, coal and medical supplies to the isolated outpost.
May 22, 1972 – Richard Nixon became the first American president to visit Moscow. Nixon and Soviet leader Brezhnev signed a pact freezing nuclear arsenals.
May 22, 1947 - The Truman Doctrine, authorizing American support for Greece and Turkey, was approved by Congress.
May 23, 1967 - Egypt blocks the Straits of Tiran, expels UN peacekeepers, and deploys its army to the Sinai Peninsula.