The author recommends zero penalties for production or use of mind-altering substances, and infinitely harsher penalties for addicts. Because people are perfectly rational beings, especially when using mind-altering substances, they'll look ahead at the penalties and decide not to be addicts. That's the author's argument, and it's obviously completely wrong.

The war on drugs has been a failure, but giving addicts the death penalty (as opposed to helping them stop being addicts) isn't very good either.