Prohibition isn't the answer. Let's talk about the merits of regulation of drugs instead.
Here in the U.S. we have higher use of cannabis than they do in the Netherlands (percentage-wise). We also have higher rates of heroin use, whereas in the U.K. they have heroin injection clinics (where junkies can get shot up in a clean supervised environment) and they have lower rates of heroin use as well. Here in the U.S., healthcare professionals have a tough time just setting up needle exchange programs.
In the United States of America, we have 5% of the world population. We have 25% of the world's prison population though, and that's largely fueled by the drug war. Did you know that we have more people locked up in America for drug charges than all of western Europe has locked up for anything? According to the two most recent surveys by CASA, high schoolers say that it's easier to get pot than alcohol. Weird, you would think that dealers would ID their young customers...
Regulating marijuana like alcohol is a no-brainer. Health costs are lower across the board for cannabis, and black market sales account for a heavy revenue percentage for the Mexican cartels. Take that away, and you take away a lot of their money.
Thoughts? This is just some of the knowledge that came to mind, I'd be happy to elaborate as the discussion continues.