Ten Years Ago Portugal Decriminalized All Drugs. Drug use went DOWN.
https://www.thefix.com/content/decrim-nation-portugal-ten-years-later
10 Reasons to legalise all drugs. 
http://www.urban75.com/Drugs/drugten.html
World Health Organization Calls for Drug Decriminalization and Broad Drug Policy Reforms 
http://www.drugpolicy.org/news/2014/07/world-health-organization-calls-drug-decriminalization-and-broad-drug-policy-reforms

I don't smoke anything. I even tried bribing my brother to stop smoking but know that only he can do that. I can't MAKE him stop & it's a foolish waste of my time and resources trying to do that. C. Everett Koop, Reagan's surgeon gen'l, said that nicotine is more addictive than heroin. Should we imprison all tobacco users? Tobacco kills more people in our society than heroin does, so why not? The two most destructive drugs in our society, tobacco & alcohol, are legal and the state even profits from them. Addiction is cheaper treated in clinics, not prisons.