Mutual suspicion had long existed between the West and the USSR, and friction was sometimes manifest in the Grand Alliance during World War II. After the war the West felt threatened by the continued expansionist policy of the Soviet Union, and the traditional Russian fear of incursion from the West continued.
|Sir Winston Churchill warned of an implacable threat that lay behind "iron curtain"|
Communists seized power in Eastern Europe with the support of the Red Army, the Russian occupation zones in Germany and Austria were sealed off by army patrols, and threats were directed against Turkey and Greece.
Conflict sometimes grew intense in the United Nations, which was at times incapacitated by the ramifications of the cold war, at others effective in dealing with immediate issues.
In a famous speech (1946) at Fulton, Mo., Sir Winston Churchill warned of an implacable threat that lay behind a Communist "iron curtain."
The United States, taking the lead against the expansion of Soviet influence, rallied the West with the Truman Doctrine, under which immediate aid was given to Turkey and Greece. Also fearing the rise of Communism in war-torn Western Europe, the United States inaugurated the European Recovery Program, known as the Marshall Plan, which helped to restore prosperity and influenced the subsequent growth of what has become the European Union.
During the cold war the general policy of the West toward the Communist states was to contain them with the hope that internal division, failure, or evolution might end their threat.
In 1948 the Soviet Union directly challenged the West by instituting a blockade of the western sectors of Berlin, but the United States airlifted supplies into the city until the blockade was withdrawn.
The challenges in Europe influenced the United States to reverse its traditional policy of avoiding permanent alliances; in 1949 the United States and 11 other nations signed the North Atlantic Treaty (NATO).
The Communist bloc subsequently formed (1955) the Warsaw Treaty Organisation as a counterbalance to NATO.