Addiction is not a disease; it is a learning disorder. We learn to use drugs because they work great; that's how learning works. But we don't learn to stop using them when they stop working; that's the disorder.
Check out episode 28: Addiction for more about dopamine, tolerance, sensitization, the nature of pleasure, and how addiction happens. All blue text is hyperlinked to sources for this episode (Addiction).
For marijuana arrest rates by race and State, see "A Tale of Two Countries: Racially Targeted Arrests in the Era of Marijuana Reform."
For US crime clearance rates as reported by the FBI, see their data HERE.
For more on the nature of Wanting versus Liking, and how they relate to addiction/Substance Abuse Disorder, see the work of Kent Berridge and Terry Robinson.
For more about the Learning Disorder model of addiction, the difference between liking and wanting, and ways to minimize your risk of addiction, check out Maia Szalavitz's incredible book Unbroken Brain.
For more on the history of the War on Drugs and addiction's relationship to social connections, check out Johann Hari's book, Chasing the Scream.