Would it be more cost effective for the government to go into the narcotic supply business?
Selling below market price  at controlled dispensaries to all adults who insist on using these mind altering products could create a profit instead of costly incarceration and prevention programs. We could use the revenue to fund treatment. It would be safer for users and victims of addicts who commit crimes to  fund their habits. Does anyone believe that price is a  factor when people want to use drugs? Would more users be created? 
Or, just say no.