George F. Kennan

George F. Kennan was in charge of long-range planning for the State Department following World War II. In July 1947, having recently returned from the Soviet Union where he had worked at the U.S. embassy in Moscow, Kennan published a letter, “The Sources of Soviet Conduct,” under the pseudonym Mr. X in the quarterly journal Foreign Affairs.

In the following viewpoint, excerpted from that letter, Kennan argues that a fundamental antagonism between communism and capitalism rule out any lasting cooperation with the Soviet Union; the Soviet Union is a rival, not a partner. Kennan thus opposes appeasement of the Soviet Union and endorses a policy of containment of Soviet expansion. He recommends that the United States apply a “counterforce” at every point where the Soviets...