Has the Drug wars been a failure?

Not a failure for the scores of 'private' prisons which rank in millions from federal contracts. Which I believe was a goal all along for the legislatures so intent on the drug wars. The US puts over 2.4 million people in prison. Almost 50% of those for what most would consider minor drug possession offenses. A bad thing if you get caught with a joint in your pocket. Good if you're a legislator getting paid under the table by the private prison industry.