"Mao finally struck in 1966 when he unleashed the Great Proletarian Cultural Revolution against the 'Four Olds': culture, ideas, customs, and habits. He mobilized millions of school and university students and sent them out against the Olds. Education collapsed as teachers and administrators were humiliated and beaten. Young Red Guards ransacked homes and destroyed ancient monuments. Together with workers they stormed Party headquarters in Shanghai and elsewhere, setting up Revolutionary Committees in their place. The army chief Lin Biao, together with Mao's wife Jiang Qing, egged them on. They finally broke into the central government compound and attacked Liu, who eventually died in captivity. Finally in 1968, Mao called off the students and sent them into the country to learn from the peasants. For most, that meant years of hard labour. The Cultural Revolution had disrupted the country and destroyed all faith in the old Communist morality. The army was supreme and its head, Lin, was now revered as Mao's heir. By now, Mao was growing old and more erratic. He rarely emerged from his quarters and his female minders controlled access to him. In 1971, Lin decided it was time for a change. He planned a coup, then tried to escape when it failed. The plane crashed and with it went much of China's faith in Chairman Mao."
January 1, 1970
https://en.wikiquote.org/wiki/Cultural_Revolution