After Roosevelt's death in April 1945, the incoming Truman administration was equally concerned with avoiding the experiences of the 1930s. President Harry S. Truman and his advisers believed that in order to avoid the mistakes of the previous decade, they had to resist the "totalitarian" Soviet Union before its appetite and power increased. In the postwar period this attitude emerged when the administration was faced with the issue of whether to share the secret of the atomic bomb with the Soviet Union or retain control for as long as possible. In arguing against sharing any knowledge with the Soviets, Secretary of the Navy James Forrestal stated that "it seems doubtful that we should endeavor to buy their understanding and sympathy. We tried that once with Hitler. There are no returns on appeasement." The Munich analogy was invoked to emphasize the futility of treating as reasonable an immoral and irrational adversary.
Another instance in which the Munich analogy came into play was the debate over the control of the Turkish Straits in August 1946. The Soviet Union proposed a joint system of control and defense by a body composed of Turkey and the other Black Sea powers, instead of Turkey retaining complete control. This proposal was met with alarm by the U.S. State Department, which saw this as an example of what was to become known as the "domino theory." This situation reminded politicians of the tumbling European dominoes of the 1930s. With loss of control in one area of Asia, the Soviet Union might move into other areas, increasing its strength along the way, which would only mean that the United States would have to fight communism later and under less favorable conditions. The Soviet Union could only be checked by employing a policy of containment, the rough intellectual outlines of which had been developed by George F. Kennan during and immediately after the war. As interpreted by Paul H. Nitze, Kennan's successor as director of the State Department's Policy Planning Staff, containment meant essentially a policy that sought to (1) block further expansion of Soviet power, (2) expose the falsities of Soviet pretensions, (3) induce a retraction of the Kremlin's control and influence, and (4) in general, foster the seeds of destruction within the Soviet system so that the Kremlin could be brought to the point of modifying its behavior to conform to generally accepted international standards. A key feature of containment envisaged the United States dealing with the Soviets from the position of strength. "In the concept of 'containment,'" noted Nitze, "the maintenance of a strong military posture is an ultimate guarantee of national security and as an indispensable backdrop to the conduct of the policy of containment." To Nitze, there was no substitute for the maintenance of superior force: "Without superior aggregate military strength, in being ready and mobilizable, a policy of 'containment'—which is in effect a policy of calculated or gradual coercion—is no more than a bluff."
The "lesson" of Munich, therefore, was to encourage firmness at all costs, even the risk of war. "Containing" Joseph Stalin was at the heart of America's Cold War.