American history is driven by periodic moments of moral convulsion. The late Harvard political scientist Samuel P. Huntington noticed that these convulsions seem to hit the United States every 60 years or so: the Revolutionary period of the 1760s and ’70s; the Jacksonian uprising of the 1820s and ’30s; the Progressive Era, which began in the 1890s; and the social-protest movements of the 1960s and early ’70s.
These moments share certain features. People feel disgusted by the state of society. Trust in institutions plummets. Moral indignation is widespread. Contempt for established power is intense.