Communism and Socialism have had an invaluable and profound effect on the Twentieth Century. These two forms of government have challenged the beliefs of other governments. They have created conflict and sparked controversy. However, these two forms of governments are influential in the fact that they have played a valuable role in shaping modern day politics.
             Communism was responsible for the Russian Revolution of 1917. The underlying causes of the Russian Revolution are rooted deep in Russia's history. For centuries, autocratic and repressive tsarist regimes ruled the country and most of the population lived under severe economic and social conditions. Russia's badly organized and unsuccessful involvement in World War I (1914-1918) added to popular discontent with the government's corruption and inefficiency. In 1917, these events resulted in the fall of the tsarist government and the establishment of the Bolshevik Party, a radical offshoot of the Russian Social Democratic Labor Party, as the ruling power. The Bolsheviks were the earliest Communists as they were renamed under the leadership of Lenin.
             The Cold War was a direct conflict of ideas between Democracy and Communism. International politics were heavily shaped by the intense rivalry between these two great blocs of power and the political ideologies they represented: democracy in the case of the United States and its allies, and Communism in the case of the Soviet bloc. While the United States accused the USSR of seeking to expand Communism in Europe and Asia, the USSR viewed itself as the leader of history's progressive forces and charged the United States with attempting to stamp out revolutionary activity wherever it arose. In 1946 and 1947, the USSR helped bring Communist governments to power in Romania, Bulgaria, Hungary, and Poland. In 1947, United States president Harry S. Truman issued the Truman Doctrine, which authorized U.S. aid to anti-Communist forces...