On the contrary, the average age of the heroin user in the Netherlands has increased since the change in status. What does that mean? It means that those who used, continue to use, and young folks aren't finding their way to heroin.
In this country, according to the DOJ's stats, young folks in the US are starting younger with drugs, and experimenting with harder stuff, like heroin and designer drugs like ecstasy.
In addition, criminalization of any substance creates demand, and exorbitant profits. Turkey did the groundwork and traced back both drugs and profit to organizations like bin Laden's.
Please name me two scotch distilleries (or rum distilleries, or Napa valley wineries) who are currently providing funding for terrorist organizations.
Whether good or bad, human nature has shown time and time again, that people (especially the young) desire that, which they are forbidden to have.
The best and only solution is to provide education, versus the blatant regurgitated government propaganda we currently have. I taught my young'ns, and NOT ONCE did it even cross my mind to get government involved in my parenting shtick.