One of the reasons why I love the Netherlands.
On a more serious note, I believe that marijuana is indeed harmless enough to be legalized. It would be like saying that you banned a stronger strain of cigarettes.
About the other drugs as I am studying them now, they do need specific supervision and monitoring. Marijuana can be treated like alcohol: "Use moderately, and don't smoke and drive"
It would be one heck of an experience if you did I think, but I wouldn't dare.