<P> From Stettin in the Baltic to Trieste in the Adriatic an "Iron Curtain" has descended across the Continent . Behind that line lie all the capitals of the ancient states of Central and Eastern Europe . Warsaw, Prague, Budapest, Belgrade, Bucharest and Sofia; all these famous cities and the populations around them lie in what I must call the Soviet sphere, and all are subject, in one form or another, not only to Soviet influence but to a very high and in some cases increasing measure of control from Moscow . </P> <P> Following the Iran crisis of 1946, Harry S. Truman declared what became known as the Truman Doctrine in 1947, promising to contribute financial aid to Greece during their Civil War and to Turkey following World War II, in the hope that this would impede the advancement of Communism into Western Europe . Later that year, diplomat George Kennan wrote an article in Foreign Affairs magazine that became known as the "X Article", which first articulated the policy of containment, arguing that the further spread of Communism to countries outside a "buffer zone" around the USSR, even if it happened via democratic elections, was unacceptable and a threat to U.S. national security . Kennan was also involved, along with others in the Truman administration, in creating the Marshall Plan, which also began in 1947, to give aid to the countries of Western Europe (along with Greece and Turkey), in large part with the hope of keeping them from falling under Soviet domination . </P> <P> In 1949, a Communist - backed government, led by Mao Zedong, was instated in China (officially becoming the People's Republic of China). The installation of the new government was established after the People's Liberation Army defeated the Nationalist Republican Government of China in the aftermath of the Chinese Civil War (1927 - 1949). Two Chinas were formed - mainland' Communist China' (People's Republic of China) and' Nationalist China' Taiwan (Republic of China). The takeover by Communists of the world's most populous nation was seen in the West as a great strategic loss, prompting the popular question at the time, "Who lost China?" The United States subsequently ended diplomatic relations with China in response to the communist takeover in 1949 . </P> <P> Korea had also partially fallen under Soviet domination at the end of World War II, split from the south of the 38th parallel where U.S. forces subsequently moved into . By 1948, as a result of the Cold War between the Soviet Union and the U.S., Korea was split into two regions, with separate governments, each claiming to be the legitimate government of Korea, and neither side accepting the border as permanent . In 1950 fighting broke out between Communists and Republicans that soon involved troops from China (on the Communists' side), and the United States and 15 allied countries (on the Republicans' side). Though the war never officially ended, the fighting ended in 1953 with an armistice that left Korea divided into two nations, North Korea and South Korea . Mao Zedong's decision to take on the U.S. in the Korean War was a direct attempt to confront what the Communist bloc viewed as the strongest anti-Communist power in the world, undertaken at a time when the Chinese Communist regime was still consolidating its own power after winning the Chinese Civil War . </P>

Domino effect in vietnam from 1965 to 1975