For much of American history, the incarceration rate was relatively low and steady, even during the turbulent 1960s. But as rising inequality took hold around 1980, so did the rise of our prison population.

Runaway inequality and the downward pressure on wages, especially for those at the bottom, create ideal conditions for a vast underground economy. Stiff sentencing laws and the War on Drugs colluded to fill our prison's and jails. For-profit private prison companies with Wall Street financing have pressed to keep the jails full and to expand them.