To liberalise or prohibit? In 2012, I joined Eliot Spitzer, Julian Assange, Vicente Fox, Russell Brand, Richard Branson and several others for an online live debate hosted by Google, YouTube, and Intelligence Squared.
For those who missed the debate, it's now online (my contribution occurs at 1:17):
For the short version, here's my position on the War on Drugs: Attacking the drug supply will never work. In the United States we spend over 20 billion dollars a year on the War on Drugs, and it's wasted money. This is because the drug supply is like a water balloon: if you push it down in one location, it comes up somewhere else. The better strategy is not to address supply, but demand. Drug demand is rooted in the brain of the addict. We know quite a bit about the circuitry and pharmacology of drug addiction, and there are many fruitful new approaches to addressing the ills of drug addiction in a cooperative, evidence-based, neurally-compatible manner. Dealing with drug addiction through rehabilitation is a more humane and cost effective idea than mass incarceration of the addicted.
For the fleshed-out version of this argument, please see my paper: Why Neuroscience Matters for a Rational Drug Policy.
Also, here's an interesting summary article of the problems with the current War on Drugs: 32 Reasons Why We Need To End The War On Drugs.
As people sometimes say, just because using drugs is a stupid idea, that doesn't automatically make the War on Drugs a smart idea.