Seventy years ago, on April 4, 1949, the United States joined the North Atlantic Treaty Organization. In his memoirs, President Harry S. Truman observed that the treaty “was the first peacetime military alliance concluded by the United States since the adoption of the Constitution.”

Ever a student of history, Truman wrote that had such an organization existed in 1914 and 1939, prior to the First and Second World Wars, “the acts of aggression that had pushed the world into two disastrous wars would not have happened.” He hoped NATO would prevent a third world war with the Soviet Union. In Article 5 of the NATO treaty, member countries agreed that an “armed attack against one or more of them in Europe or North America shall be considered an attack against them all….” In the event of such an attack, they would collectively take action as deemed necessary, “including the use of armed force….”

President Truman, as he often did, let others claim the spotlight. On April 4, 1949, Secretary of State Dean Acheson, not Truman, signed the NATO treaty on behalf of the United States. In his memoirs, Acheson quipped that at the signing ceremony the Marine Band ironically played “I’ve Got Plenty of Nothin’” and “It Ain’t Necessarily So,” songs from the musical “Porgy and Bess.” In addition to the United States and Canada, ten European nations initially joined NATO.

Several factors contributed to President Truman and Congress agreeing to U.S. membership in NATO. After the end of World War II in 1945, the United States and its Western European allies increasingly felt threatened by the Soviet Union, which took political control of Eastern Europe and sought to expand communism into Western Europe. In 1948, a Soviet-inspired coup in Czechoslovakia deposed the democratic government, and in Berlin, the Soviet Union blockaded land and rail entry into the city. Both events increased tensions between east and west and accelerated passage of Marshall Plan economic aid to European countries. These events persuaded President Truman and western leaders that the Soviet Union must be resisted by military means, if necessary.

Congress agreed. In June 1948, the Senate passed the Vandenberg Resolution, which supported regional and collective self-defense associations in the interest of U.S. national security. The resolution was the namesake of Arthur Vandenburg, a Republican U.S. senator from Michigan. As chairman of the Senate Foreign Relations Committee, Vandenburg supported the Truman administration’s internationalist approach to containing Soviet expansion and aggression. On July 21, 1949, the Senate voted in support of the treaty, 82-13. In his memoirs, Truman noted that Congress wanted assurances that Europe would “carry an appropriate share of the burden of common defense.” According to a 1963 NATO document located at https://www.nato.int/nato_static_fl2014/assets/pdf/pdf_1963_12/20100830_1963-002.pdf, the U.S. paid for over 72% of NATO’s defense spending in 1949, a year when Europe was still recovering from World War II.

One of the main stumbling blocks in creating NATO concerned the role of Germany in the alliance. Memories of World War II were still fresh, and French leaders resisted efforts to rearm Germany. Acheson and others insisted that West Germany, which was established in 1949, had to be militarily strong enough to resist a Soviet invasion. In an oral history interview transcript that is available on the Harry S. Truman Library’s website at https://trumanlibrary.org/oralhist/frankso.htm, Oliver Franks, British ambassador to the United States, recognized, “You simply could not set up a viable military defense of Western Europe without the Germans.” The agreement to appoint an American as NATO supreme commanders helped ease European concerns about the resurgence of German aggression. In December 1950, Dwight Eisenhower was appointed NATO’s first supreme commander.

In 1999, Poland, Hungary and the Czech Republic joined NATO. The foreign ministers of these three countries, along with U.S. Secretary of State Madeleine Albright, attended an accession ceremony hosted by the Harry S. Truman Library. The table used for the occasion was the same one that Harry Truman used when he approved the Greek-Turkish aid bill in 1947. President Lyndon Johnson also used it when he signed the Medicare Act at the Truman Library in 1965. That table is on display at the Truman Library.

Sam Rushay is the supervisory archivist of the Harry S. Truman Library and Museum in Independence.