The United States had a long history of avoiding foreign alliances that might require the commitment of its troops abroad. However, in accepting the realities of the post-World War II world, in which traditional powers like Great Britain or France were no longer strong enough to police the globe, the United States realized that it would have to make a permanent change in its foreign policy, shifting from relative isolation to active engagement.

With Germany’s defeat imminent, the Allies set terms for unconditional surrender. At the same time, deliberation began over reparations, tribunals, and the nature of an occupation regime that would initially be divided into American, British, French, and Soviet zones. Suspicion and mistrust were already mounting. The political landscape was altered drastically by Franklin Roosevelt’s sudden death in April 1945, just days before the inaugural meeting of the UN. Although Roosevelt was skeptical of Stalin, he always held out hope that the Soviets could be brought into the “Free World.” Truman had no such illusions. He committed the United States to a hard-line, anti-Soviet approach.

On assuming the office of president, Harry Truman was already troubled by Soviet actions in Europe. He disliked the concessions made by Roosevelt at Yalta, which had allowed the Soviet Union to install a Communist government in Poland. At the Potsdam conference, held from July 17 to August 2, 1945, Truman also opposed Stalin’s plans to demand large reparations from Germany.

Figure 1. At the postwar conference in Potsdam, Germany, Harry Truman stands between Joseph Stalin (right) and Clement Atlee (left). Atlee became prime minister of Great Britain, replacing Winston Churchill, while the conference was taking place.

The Cold War

Although the United States and the Soviet Union did finally reach an agreement at Potsdam, this was the final occasion on which they cooperated for quite some time. Each remained convinced that its own economic and political system was superior to the other’s, and the two superpowers quickly found themselves drawn into conflict. The decades-long struggle between them for technological and ideological supremacy became known as the Cold War. So called because it did not include direct military confrontation between Soviet and U.S. troops, the Cold War was fought with a variety of other weapons: espionage and surveillance, political assassinations, propaganda, and the formation of alliances with other nations. It also became an arms race, as both countries competed to build the greatest stockpile of nuclear weapons, and proxy wars were fought on their behalf, primarily by the citizens of poorer nations, such as Korea and Vietnam.

Containment Abroad

The “Long Telegram”

In February 1946, George Kennan, a State Department official stationed at the U.S. embassy in Moscow, sent an eight-thousand-word message to Washington, DC. In what became known as the “Long Telegram,” Kennan maintained that Soviet leaders believed that the only way to protect the Soviet Union was to destroy “rival” nations and their influence over weaker nations. According to Kennan, the Soviet Union was not so much a revolutionary regime as a totalitarian bureaucracy that was unable to accept the prospect of a peaceful coexistence with the United States. He advised that the best way to thwart Soviet plans for the world was to limit Soviet influence—primarily through economic policy—to those places where it already existed and prevent its political expansion into new areas. This strategy, which came to be known as the policy of containment, formed the basis for U.S. foreign policy and military decision making for more than thirty years.

The Domino Theory and the Iron Curtain

As communist governments came to power elsewhere in the world, American policymakers extended the rationale of containment to what became known as the domino theory under the Eisenhower administration: Neighbors to communist nations, so was the assumption, were likely to succumb to the same allegedly dangerous and infectious ideology. Like dominos toppling one another, entire regions would eventually be controlled by the Soviets. The demand for anti-communist containment appeared as early as March 1946 in a speech by Winston Churchill, in which he referred to an Iron Curtain that divided Europe into the “free” West and the communist East controlled by the Soviet Union.

The commitment to containing Soviet expansion made necessary the ability to mount a strong military offense and defense. In pursuit of this goal, the U.S. military was reorganized under the National Security Act of 1947. This act streamlined the government in matters of security by creating the National Security Council and establishing the Central Intelligence Agency (CIA) to conduct surveillance and espionage in foreign nations. It also created the Department of the Air Force, which was combined with the Departments of the Army and Navy in 1949 to form one Department of Defense.

The Marshall Plan

By 1946, the American economy was growing significantly. At the same time, the economic situation in Europe was disastrous. The war had turned much of Western Europe into a battlefield, and the rebuilding of factories, public transportation systems, and power stations progressed exceedingly slowly. Starvation loomed as a real possibility for many. As a result of these conditions, communism was making significant inroads in both Italy and France. These concerns led Truman, along with Secretary of State George C. Marshall, to propose to Congress the European Recovery Program, popularly known as the Marshall Plan. Between its implantation in April 1948 and its termination in 1951, this program gave $13 billion in economic aid to rebuild European nations.

Watch It

This video summarizes the goals of the Marshall Plan and how the plan led to increased tensions with the Soviet Union.

You can view the transcript for “What Was the Marshall Plan? | History” here (opens in new window).

The Economic, Political, and Humanitarian Motivations of the Marshall Plan

Truman’s motivation was economic and political, as well as humanitarian. The plan stipulated that the European nations had to work together in order to receive aid, thus enforcing unity through enticement, while seeking to undercut the political popularity of French and Italian Communists and dissuading moderates from forming coalition governments with them. Likewise, much of the money had to be spent on American goods, boosting the postwar economy of the United States as well as the American cultural presence in Europe. Stalin regarded the program as a form of bribery. The Soviet Union refused to accept aid from the Marshall Plan, even though it could have done so, and forbade the Communist states of Eastern Europe to accept U.S. funds as well. Those states that did accept aid began to experience an economic recovery.

Try It

George C. Marshall and the Nobel Peace Prize

The youngest child of a Pennsylvania businessman and Democrat, George C. Marshall chose a military career. He attended the Virginia Military Institute, was a veteran of World War I, and spent the rest of his life either in the military or otherwise in the service of his country, including as President Truman’s Secretary of State. He was awarded the Nobel Peace Prize in 1953, the only soldier to ever receive that honor. Below is an excerpt of his remarks as he accepted the award.

Figure 2. During World War II, George C. Marshall was responsible for expanding the 189,000-member U.S. Army into a modern, fighting force of eight million by 1942. As Secretary of State under Truman, he proposed the European Recovery Program to aid European economies struggling after the war.

There has been considerable comment over the awarding of the Nobel Peace Prize to a soldier. I am afraid this does not seem as remarkable to me as it quite evidently appears to others. I know a great deal of the horrors and tragedies of war. Today, as chairman of the American Battle Monuments Commission, it is my duty to supervise the construction and maintenance of military cemeteries in many countries overseas, particularly in Western Europe. The cost of war in human lives is constantly spread before me, written neatly in many ledgers whose columns are gravestones. I am deeply moved to find some means or method of avoiding another calamity of war. Almost daily I hear from the wives, or mothers, or families of the fallen. The tragedy of the aftermath is almost constantly before me.

I share with you an active concern for some practical method for avoiding war. . . . A very strong military posture is vitally necessary today. How long it must continue I am not prepared to estimate, but I am sure that it is too narrow a basis on which to build a dependable, long-enduring peace. The guarantee for a long continued peace will depend on other factors in addition to a moderated military strength, and no less important. Perhaps the most important single factor will be a spiritual regeneration to develop goodwill, faith, and understanding among nations. Economic factors will undoubtedly play an important part. Agreements to secure a balance of power, however disagreeable they may seem, must likewise be considered. And with all these there must be wisdom and the will to act on that wisdom.

What steps did Marshall recommend be taken to maintain a lasting peace? To what extent have today’s nations heeded his advice?