Because of the political decisions made decades ago to criminalize possession of even small amounts of marijuana, cocaine et al, the prison population surged. Right now, today, in the United States, there are 2.3 million people behind bars. Bizarrely, by criminalizing so many petty drug crimes, and growing the prison population, the prison-industrial complex in this country is a huge industry which has enjoyed large growth rates. There is one person employed in the prison-industrial complex for each person behind bars.
[Source: A Plague of Prisons: The Epidemiology of Mass Incarceration in America by Ernest Drucker (five stars).]