The next year, they created the Communist International (Comintern) to control the Communist movement throughout the world. After the Comintern's dissolution in 1943, the Soviet party's Central Committee continued to use Communist parties from other nations as instruments of Soviet foreign policy. Each national party was required to adhere to the Leninist principle of subordinating members and organizations unconditionally to the decisions of higher authorities.
In 1922 the Comintern forced the two American parties, which consisted of about 12,000 members, to amalgamate and to follow the party line established in Moscow. Although membership in the American party rose to about 75,000 by 1938, following the Great Depression, many members left the party after the signing of the Nazi-Soviet Nonaggression Pact of 1939. Others left in 1956 after Nikita Khrushchev exposed some of Stalin's crimes and Soviet forces invaded Hungary. Only the hard-core members remained after such reversals of Soviet policy. The American party, a significant although never major political force in the United States, became further demoralized when Boris Yeltsin outlawed the Communist party in Russia in August 1991 and opened up the archives, revealing the continued financial as well as ideological dependency of the American Communists on the Soviet party up until its dissolution.