Study the history. Drugs were banned the same state moralists who wanted prohibition. Everything causes problems. The State's war on drugs causes a heck of a lot of problems - more so than the drugs themselves ever caused.
If you read the article, the author doesn't promote wholesale legalization, but common sense methods of ending the madness that is the war on drugs.
YOU just proved my point.
Thanks (you're making this TOO EASY).
Now, if you could just do something about the stupid people in our society/world ....