So far, I haven't weighed in on this discussion. Personally, I don't use any drug that my physician hasn't prescribed. I do take medications for cholesterol, high blood pressure, and type II diabetes. The fact is that our war on drugs is as much of a failure as Prohibition was. All it has accomplished has been to enrich criminals, engender gang violence, put a lot of folks in jail who could be on the streets with no more danger to society than that which we face from social drinkers, and use up a lot prison space better filled with robbers, rapists, etc.
In 5,000 years of human history, laws against the possession and use of inanimate objects and substances have proven to be singularly ineffectual if a good proportion of society wants them. Note that the term "good proportion" does not mean even a majority, just a sizable minority. The reason why we don't abandon the War on (some) Drugs is because, first, some people are making too good of a living off of it. Think about the lawyers and other such folks who make a lot of money off of this policy. Second, the politicians want every American to be guilty of something because that makes us easier to control. It gives the government a club to hold over more heads. Read Ayn Rand's "Atlas Shrugged."