Following the failure of the Great Leap Forward, Mao began to denounce the development of “new bourgeois elements” among the party and technical elites in both the Soviet Union and China. Adapting the Marxist-Leninist theory of “permanent revolution,” he proclaimed that “protracted, complex, and sometimes even violent class struggle” would be constant elements of the revolution until the final stage of socialism was achieved.

In 1966, Mao announced a program that was officially intended to reaffirm the core values of Chinese communism and attack creeping bourgeois tendencies in the party bureaucracy: the Great Proletarian Cultural Revolution. Its unofficial purpose was to purge the party leadership of anyone who opposed him.

Mao closed schools and invited student groups to join paramilitary Red Guard units. Working under the slogan “fight selfishness, criticize revisionism,” the Red Guard burned books, destroyed Confucian and Buddhist temples, and hunted down “counter-revolutionaries.” Revisionists, intellectuals, and anyone suspected of “ideological weakness” (code for disagreeing with Mao) were all fair targets.

Some were punished with nothing worse than wearing a dunce cap and publicly confessing their errors. Others were beaten, tortured, killed, or driven to commit suicide. Urban residents, intellectuals, and government officials were relocated to the country to “learn from the peasants.” The worst of the Cultural Revolution ended with Mao's death in 1976.