The word Communism has been used in different senses by different authors, but from 1917 onward it was most readily associated with the type of political and economic system established in Russia and the other lands that became the Union of Soviet Socialist Republics (USSR). By the 1970s Communism in this sense of the term prevailed in Latvia, Lithuania, Estonia, and parts of Bessarabia, all of which were incorporated directly into the USSR, as well as in Mongolia, Poland, Hungary, Czechoslovakia, Bulgaria, Romania, Yugoslavia, Albania, East Germany, North Korea, China, Tibet, Cuba, Vietnam, Laos, and Cambodia. A number of other states, including Nicaragua, Granada, Afghanistan, Angola, Mozambique, and Ethiopia, were ruled by parties closely allied with the USSR, but whether they were full-fledged Communist states is open to debate. In addition, parties advocating the Soviet model of government formed in most other countries. These states and parties, although they...