The historical experience of socialist construction in the Soviet Union and the People's Democracies of Europe confirmed that class struggle continues during socialist construction, which means that a counterrevolution is possible.
The attempts to overthrow the workers' power in a number of European countries (counterrevolutionary attempted coup in the GDR in 1953, attempted counterrevolutions in Hungary in 1956, Czechoslovakia in 1968 and Poland in 1980-81) was nothing other than efforts of the defeated bourgeois classes of these countries to retake power. These efforts, as we shall see below, were strongly supported by international imperialism in a multifaceted way.
