A City Guide To Yan‚„an for Marxist theories led to the introduction of communism in the SOVIET UNION, CHINA, CUBA, and much of Eastern Europe. Most Western countries contain elements of socialist thought, and socialist parties continue to thrive. In the UNITED STATES, however, socialist thought never gained prominence. While socialists were active in the 1920s and the Communist Party of the USA was a definite presence in the United States during the 1930s, SOCIALISM was virtually nonexistent after August 1939, when the Soviet Union signed a non-aggression pact with GERMANY as WORLD WAR II began, leaving American socialists stunned and disillusioned. Many reasons have been given for the absence of socialism in the United States. In the early days of the INDUSTRIAL REVOLUTION, land was still plentiful, so people could always go west instead of working for subsistence wages in a factory. The United States also has a relatively open class system and universal suffrage, and Democrats and Republicans have a tendency to incorporate third-party platforms, so American workers have never felt alienated from the political and economic systems in the way that Marx predicted. A City Guide To Yan‚„an 2016.