The US puts a larger percentage of its population behind bars than any other country.
Commonly acknowledged, but wrongly. Look at the inflection points in the U.S. incarceration rate: https://upload.wikimedia.org/wikipedia/commons/4/48/U.S._inc...
Growth started in 1972-73. The growth rate kneed around 2000. Compare with the prison prison population: http://static.prisonpolicy.org/prisonindex/graphs/privatepri.... They were pretty much insignificant until the 1990's. By then, the growth trend in incarceration rates was firmly established, and indeed, was closer to the knee in 2000 than to the initial upswing in the 1970's.
What happened in the 1980's and 1990's? Privatization of many other government services: http://www.kevingunn.org/wp-content/uploads/2012/08/TotalFed....
The most reasonable conclusion from the data is that private prisons are not creating the demand for prisoners, but rather reacting to the demand for privatizing government services generally. I fully agree that private prisons should be illegal, but they didn't create the problem.
We created the problem, with three strikes laws and cracking down on probation. E.g. http://www.dc.state.fl.us/secretary/press/2001/timeserved.ht.... In 1991, Florida prisoners served about 35% of their sentences. Due to a state law, by 2001 it was 83%.
[0]http://www.bop.gov/about/statistics/statistics_inmate_offens...
edit: As pointed out below it was the federal prison pop. Also, made it more obvious that I didn't mean 50% of America's total population.
I think people too readily accept the narrative that crime in the U.S. can be traced back to the drug war.
Here is drug war spending: http://cdn.thewire.com/media/old_wire/img/upload/2012/10/12/...
Here is violent crime rate: http://www.urban.org/sites/default/files/wp-content/uploads/...
Violent crime started trending up in 1963, about 8 years before Nixon declared the war on drugs. By the time the drug war really got going in 1982-86, violent crime rates had already tripled.
The Drug War and school-to-prison pipleline are real, too. We farm black people to keep no-neck white men in "good jobs at good wages." If anything, the Drug War is preventing a further drop in crime as lead gets flushed out of the environment.
There is no conclusive proof or even extensive evidence in favor of any of those theories. But I think the drug war theory is one of the less compelling explanations given the evidence we have.
They are pretty compelling. Lead wasn't just about crime. Tetraethyl lead was almost a global disaster that might have cost humanity dearly in some very general ways. The hypothesis is very strong, too. Refinery workers went violently insane. There was no question what the effect would be if there was enough cause to cause it.
Stop and ask yourself: is there anyone who regularly writes on HN who thinks the drug war is a good thing? If you took a poll of HN commenters, full legalization would come out, where, 98%?
Clearly, when we discuss prison and the drug war, we're all talking about something more subtle than whether we should imprison people for doing drugs.
Unfortunately, while the libertarians might make HN look wise about the Drug War, there are way too many people, even on HN, who are happy with, and who have various justifications for, prisons filled with black and latino prisoners.