The roots of the Cold War stretched back several decades. After the Bolshevik Revolution of 1917, the United States refused to grant diplomatic recognition to the Soviet Union and sent troops to Russia to support anti-Bolshevik forces seeking to overturn the revolution, an effort that failed. At the same time, the American government, fearing Communist efforts to overthrow capitalist governments, sought to wipe out Communism in the United States by deporting immigrant radicals during the Red scare (see “The Red Scare, 1919–1920” in chapter 21). The United States continued to deny diplomatic recognition to the USSR until 1933, when President Roosevelt reversed this policy. Nevertheless, relations between the two countries remained uneasy.

World War II brought a thaw in tensions. President Roosevelt went a long way toward defusing Stalin’s concerns at the Yalta Conference in 1945. The Soviet leader viewed the Eastern European countries that the USSR had liberated from the Germans, especially Poland, as a buffer to protect his nation from future attacks by Germany. Roosevelt understood Stalin’s reasoning and recognized political realities: The Soviet military already occupied Eastern Europe, a state of affairs that increased Stalin’s bargaining position. Still, the president attempted to balance Soviet influence by insisting that the Yalta Agreement include a guarantee of free elections in Eastern Europe.

By contrast, Roosevelt’s successor, Harry S. Truman, took a much less nuanced approach to U.S.-Soviet relations than his predecessor. Stalin’s ruthless purges within the Soviet Union in the 1930s and 1940s convinced Truman that the Soviet dictator was paranoid and extremely dangerous. He believed that the Soviets threatened “a barbarian invasion of Europe,” and he intended to deter it. In his first meeting with Soviet foreign minister Vyacheslav Molotov in April 1945, Truman rebuked the Russians for failing to support free elections in Poland. Molotov, recoiling from the sharp tone of Truman’s remarks, replied: “I have never been talked to like that in my life.”

Despite this rough start, Truman did not immediately abandon the idea of cooperation with the Soviet Union. At the Potsdam Conference in Germany in July 1945, Truman and Stalin agreed on several issues. The two leaders reaffirmed the concept of free elections in Eastern Europe; Soviet troop withdrawal from the oil fields of northern Iran, which bordered the USSR; and the partition of Germany (and Berlin itself) into four Allied occupation zones.

Within six months of the war’s end, however, relations between the two countries soured. The United States was the only nation in the world with the atomic bomb and boasted the only economy reinvigorated by the war. As a result, the Truman administration believed that it held the upper hand against the Soviets. With this in mind, the State Department offered the Soviets a $6 billion loan, which the country needed to help rebuild its war-ravaged economy. But when the Soviets undermined free elections in Poland in 1946 and established a compliant government, the United States withdrew the offer. Soviet troops also remained in northern Iran, closing off the oil fields to potential capitalist enterprises. The failure to reach agreement over international control of atomic energy proved the last straw. The United States wanted to make sure it would keep its atomic weapons, while the Soviets wanted the United States to destroy its nuclear arsenal. Clearly, the former World War II allies did not trust each other.

Truman had significantly underestimated the strength of the Soviet position. The Soviets were well on their way toward building their own atomic bomb, negating the Americans’ nuclear advantage. The Soviets could also ignore the enticement of U.S. economic aid by taking resources from East Germany and mobilizing the Russian people to rebuild their country’s industry and military. Indeed, on February 9, 1946, Stalin delivered a tough speech to rally Russians to make sacrifices to enhance national security. By asserting that communism was “a better form of organization than any non-Soviet social system,” he implied, according to George Kennan, that capitalist nations could not coexist with communism and that future wars were unavoidable unless communism triumphed over capitalism.

Whether Stalin meant this speech as an unofficial declaration of a third world war was not clear, but U.S. leaders interpreted it this way. A few days after Stalin spoke, Kennan sent an 8,000-word telegram from the U.S. Embassy in Moscow to Washington, blaming the Soviets for stirring up international tensions and confirming that Stalin could not be trusted. The following month, on March 15, former British prime minister Winston Churchill gave a speech in Truman’s home state of Missouri. Declaring that “an iron curtain has descended across the Continent” of Europe, Churchill observed that “there is nothing [the Russians] admire so much as strength, and there is nothing for which they have less respect than for . . . military weakness.” This comment reaffirmed Truman’s sentiments expressed the previous year: “Unless Russia is faced with an iron fist and strong language another war is in the making.” The message was clear: Unyielding resistance to the Soviet Union was the only way to avoid another world war.

Not all Americans agreed with this view. Led by Roosevelt’s former vice president Henry Wallace, who served as Truman’s secretary of commerce, critics voiced concern about taking a “hard line” against the Soviet Union. Stalin was pursuing a policy of expansion, they agreed, but for limited reasons. Wallace claimed that the Soviets merely wanted to protect their borders by surrounding themselves with friendly countries, just as the United States had done by establishing spheres of influence in the Caribbean. Except for Poland and Romania, Stalin initially accepted an array of governments in Eastern Europe, allowing free elections in Czechoslovakia, Hungary, and, to a lesser extent, Bulgaria. Only as Cold War tensions escalated did the Soviets tighten control over all of Eastern Europe. Critics such as Wallace considered this outcome the result of a self-fulfilling prophecy; by misinterpreting Soviet motives, the Truman administration pushed Stalin to counter the American hard line with a hard line of his own.

Thus, after World War II, the United States came to believe that the Soviet Union desired world revolution to spread communism, a doctrine hostile to free market individualism. At the same time, the Soviet Union viewed the United States as seeking to make the world safe for capitalism, thereby reducing Soviet chances to obtain economic resources and rebuild its war-shattered economy. Each nation tended to see the other’s actions in the most negative light possible and to see global developments as a zero-sum game, one in which every victory for one side was necessarily a defeat for the other.