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Start of the Cold War - The Berlin airlift and the creation of NATO

Learn about the Berlin airlift, NATO, and the National Security Act.


  • Tensions between the United States and the Soviet Union came to a head in 1948, when the Soviet Union blockaded Berlin and the United States led a year-long airlift to supply citizens stranded in the western zone of the city.
  • Realizing that conflict with the Soviet Union might escalate into war, the United States joined the North Atlantic Treaty Organization (NATO) defensive alliance and ramped up security measures at home with the National Security Act.

The Berlin airlift

The growing tensions between the United States and the Soviet Union finally erupted into crisis in 1948. For three years, the Big Four powers had followed the plan of occupation decided at Yalta, with each power administering a zone of Germany as well as a zone of the capital city of Berlin. But ideological divisions over what should be done with Germany tore the former allies apart.
Believing that a reunified Germany would prevent a repeat of the economic catastrophe that had followed World War I, the United States, Britain, and France decided to consolidate their zones of Germany. The Soviet Union, which wanted to ensure that Germany could never attack it again, strongly objected to this plan. In 1948 the Soviet Union flexed its might by cutting off all highway and railroad access to the city of Berlin (which fell within its occupation zone), hoping to absorb all of Berlin under Soviet control. West Berlin would either starve or the Western Allies would surrender to the Soviets' wishes for Germany.start superscript, 1, end superscript
Map of partitioned Germany showing the nations in control of each region: England in the northwest, France in the southwest, the United States in the southeast, and the Soviet Union in the northeast. The city of Berlin falls within the Soviet zone.
Map of partitioned Germany showing the nations in control of each region: England in the northwest, France in the southwest, the United States in the southeast, and the Soviet Union in the northeast. Note that the city of Berlin, which was itself divided among the four powers, fell within the Soviet region. Image credit: Wikimedia Commons
The United States, Britain, and France refused to allow the Soviet Union to hold Berlin hostage. Instead, they arranged for a massive support mission to supply West Berlin. From June 1948 to May 1949, they sent hundreds of airplanes filled with food and fuel every day, in what became known as the Berlin airlift. They also instituted a counter-blockade on East Berlin.squared
After 11 months, the Soviets realized that the blockade was a failure and ended it. But the standoff over Berlin had crystallized the divisions of the Cold War. The Western Allies turned their combined occupation zones into the new country of West Germany, and the Soviet Union responded by creating East Germany. The Soviets also began the process of building a barrier between the eastern and western zones of Berlin that would stand for the next forty years.cubed

NATO and the National Security Act

As tensions raged in Europe, the United States realized that long-lasting peace was not going to follow on the heels of World War II. When Britain, Belgium, The Netherlands, and Luxembourg asked the United States to join its defensive alliance in 1948, the United States broke its longstanding aversion toward entangling alliances abroad and signed on.start superscript, 4, end superscript
The North Atlantic Treaty Organization (NATO), as the pact was named, started with 12 member nations (today, it has 30). NATO promised that an attack on one of its members would provoke a response from all of its members. NATO became the major international body opposing communism in the twentieth century.start superscript, 5, end superscript
The United States also strengthened its commitment to defense at home. In 1947 Congress passed the National Security Act, which united the branches of the armed services under the new Department of Defense. It also created the Central Intelligence Agency and the National Security Council to gather intelligence and advise the president on foreign policy. In addition, Congress reinstituted the Selective Service military draft for young men in 1948. If any hope remained that the world would be tranquil after Hitler's defeat, by the end of the 1940s it had gone. start superscript, 6, end superscript

What do you think?

Why do you think the United States was so determined to help West Berlin when it had no real interests to protect there?
Do you think it was a good idea for the United States to join NATO? What are the potential benefits and drawbacks of being part of a defensive alliance?

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