"Was it a ploy to get rid of the Red Guards, who were slipping out of his grasp?"

Red Guards
Public DomainRed Guards - Credit: Villa Giulia
 Red Guards were a mass movement of civilians and soldiers, mostly students and other young people, in the People's Republic of China (PRC). They were mobilized by Mao Zedong in 1966 and 1967, during the Cultural Revolution. Red Guards marched across China in a campaign to eradicate the 'Four Olds'. Old books and art were destroyed, museums were ransacked, and streets were renamed with new revolutionary names and adorned with pictures and the sayings of Mao. Many famous temples, shrines, and other heritage sites in Beijing were attacked. However, attacks on culture quickly descended into attacks on people. Ignoring guidelines in the 'Sixteen Articles' that stipulated that persuasion rather than force was to be used to bring about the Cultural Revolution, Red Guards subjected officials in positions of authority and perceived 'bourgeois elements' to physical and psychological attacks. 

As Mao Zedong grew more powerful, he became increasingly paranoid and he initiated several changes to secure his own position within the party. One of these was the disbandment of the Red Guards in 1968. Mao ordered the Chinese People's Liberation Army to put an end to the Red Guards.

Below is the Red Guards Battle Song. Throughout the video, one can see the Red Guards taking down "Old" elements of Chinese culture, including signs written in Traditional Characters. One of the main results of the Cultural Revolution was the Communist Redesign of the Chinese language. Old characters (traditional) were destroyed while new ones (simplified) replaced them. Traditional characters are still used in Taiwan and Hong Kong. Many lament that simplified characters lack depth and beauty.