Series: Origins of the Cold War

The mutual antagonism of the Soviets and Americans, leading to the Cold War, developed after World War II as the two sides competed over a number of geographic and political zones of contention. In several confrontations and diplomatic situations, American policymakers in particular learned important lessons, including that the Soviet Union was no longer an ally, that Moscow intended to expand the physical realm of communism, and that the Soviets could only be deterred by force and the threat of force.

Two major conferences—Yalta and Potsdam—were held in 1945 with the Soviets, British, and Americans to determine the fate of Europe and defeated Germany. The Yalta Conference, at the Russian Black Sea resort in February, was the last meeting of the Big Three allied leaders—American President Franklin D. Roosevelt, British Prime Minister Winston Churchill, and Soviet Premier Joseph Stalin. At the conference, debates over Poland’s postwar borders and government put Roosevelt and Churchill at odds with Stalin. Within months of Yalta, Soviet control over Poland and the rest of Eastern Europe had evolved into a serious concern for the future of Western Europe.

Leaders of the three countries met again at the Potsdam Conference, outside of the captured Berlin, from 17 July to 2 August 1945. This was the last major conference of World War II, and its participants attempted to build upon the efforts of the Yalta Conference. However, the United States and Britain found themselves again unable to come to an agreement on many diplomatic issues with the Soviet Union. President Harry S. Truman, who had taken office following Roosevelt’s death on 12 April 1945, and many Potsdam attendees, saw the Soviet Union shifting from a wartime ally, even a frequently difficult one, to an outright adversary.

The postwar battle over the control of Germany and Berlin demonstrates how tensions evolved dividing Europe into East versus West. Germany was physically and ideologically divided between the two sides. For the United States, a strong rebuilt Germany capable of sustaining its own redevelopment while supporting its neighbors seemed vital to the success of Western Europe, while Soviet leaders longed for a ravaged Germany, incapable of ever again attacking the East. The superpowers’ division over Germany’s fate was centered symbolically on the country’s former capital, Berlin. The United States, Britain, France, and the Soviet Union each had military troops stationed in Berlin—110 miles into the heart of the Soviet occupation zone and the future East Germany—and their presence led to the 1948 Berlin Blockade.

American financial assistance toward the reconstruction of Europe following the war also contributed to a deteriorating relationship between the United States and the Soviet Union. The United States emerged from the war with a strong economy, and was in the position to provide aid to Europe, a situation ultimately resented by the Soviets. Initially the United States offered aid on a country- by- country basis, with $3.75 billion going to the British in 1945-46 and $1.2 billion to France the following year. The Soviets requested $1 billion in aid in 1945, but due to crumbling East-West relations, the Truman Administration never formally approved an aid package for Moscow. State Department officials claimed to have “lost” the Soviet request, though later historians have proved their story was fabricated so as to provide justification for rejecting Moscow’s plea. No matter the reason, Moscow’s failure to garner American postwar aid proved a contentious issue in Soviet-American dealings.

The United States also faced conflict with the Soviets outside of Europe. The fate of China, for example, as a result of its civil war, was of crucial interest to the two superpowers if for no other reason than its status as the world’s most populous country. Led by Mao Zedong, China’s Communists eventually won power, leading to greater American concerns over the future of the capitalist system without its most populous member and to domestic attacks against the Truman Administration for “losing” China. Communism’s victory in this crucial early Cold War battle helped American policymakers understand the growing threat of this dangerous new ideology and gave the United States a new and bitter adversary in Asia.

The Iranian Crisis of 1946 also contributed to the polarization of Soviet-American relations. Following World War II the Soviets agreed to end their occupation of northern Iran and remove their troops within six months of the conflict’s end. When the Soviets did not comply with their wartime promise and continued to occupy northern Iran and use political and military pressure to gain oil concessions, President Truman threatened war and mobilized troops to the area. These actions forced the Soviets to withdraw without concessions, offering proof to American policymakers that the Soviets responded only to force. By 1947, therefore, tensions ran high between the East and West and American leaders had developed an increasingly hostile view of Russia.