:0) Let's start from here ..
"The number of people behind bars for nonviolent drug law offenses increased from 50,000 in 1980 to over 400,000 by 1997."
Now let's talk about violent crime, which is different, and not the cause of the explosion of incarceration .. which is intuitive reading from your chart.
US crime rate at lowest point in decades. Why America is safer now. - CSMonitor.com
The crime rate for serious crimes, including murder, rape, and assault, has dropped significantly since the early 1990s in part because of changes in technology and policing, experts say.
... four main reasons for the decline:
. Increased incarceration, including longer sentences, that keeps more criminals off the streets.
. Improved law enforcement strategies, including advances in computer analysis and innovative technology.
. The waning of the crack cocaine epidemic that soared from 1984 to 1990, which made cocaine cheaply available in cities across the US.
. The graying of America characterized by the fastest-growing segment of the US population – baby boomers – passing the age of 50.
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Perhaps you can tell me how this changes the equation that
the explosion of incarceration in the US is directly related to the war on drugs, the vats majority of which are for non-violent crimes.