Among developed economies, the United States has the most restrictive policy relative to illicit drug. The Netherlands have a much more relaxed one. Guess where more people use drugs.
According to a study published in PLos Medecine, Americans are far ahead of anybody else. this table shows that 16.2% have tried cocaine, New Zealand is second at 4.3%, and the liberal Netherlands have 1.9%. For cannabis, it is 42.4, 41.9% and 19.8%.
So much for the war on drugs. This shows that markets are much more powerful than regulation, they find a way to circumvent rules and laws. How can one really reduce drug use, if this is the true goal? Make it legal, thus reducing its price, as the risk premium drops. Supply will then drop. If the price goes too low, tax it like tobacco and alcohol. At least revenue would then end up in the pockets of the government instead of crooks.