Alot of good points here. Let me share my experiences from when I was a little less mature.
In high school I smoked pot. The worst that happened to me was that I fell asleep in class. The people who drank got into far more trouble than the stoners. I stopped on my own after high school.
When I got into college I started snorting Ritalin. Man it was great high. Of course it was expensive and as stressed as I was in college, I just couldn't handle it. I was also having problems with my bipolarisim (Family history of mental disease, not from drug use.) from the stress so I more or less stopped snorting. (Again, on my own.) It would be kinda nice to be able to get a snort of it on a day off without going to jail.
Today, the only drug I use is gunpowder.
There are two types of drug users. Those who control the drug use and those whose drug use controls them. The second type is the one that makes the news. You never hear about the first kind, about peole like me, who dabbled in it and then moved onto other things or continued to use in moderation. Making it legal would help the person who has a problem get help. It would also allow the government to monitor purity and ensure safe dosing.