"My thinking tends to be libertarian. That is, I oppose intrusions of the state into the private realm—as in abortion, sodomy, prostitution, pornography, drug use, or suicide, all of which I would strongly defend as matters of free choice in a representative democracy."
a different CP

I guess the real question is: Are drug laws really benefitting society?

I think the point's been beaten in, and it's pretty tough to change people's minds on it. I guess that's why I rarely participate in here... Hmmm...

I disagree that SS has been beneficial to society, but that's another story.

GD, while the problems with the current system are undeniable, I think it is impossible to predict all of the problems that would arise from legalization. I have listed many that I do no think are far fetched whatsoever, and I am certain there are those that I have not even considered.

Legalization is no panacea, and is at best a trade off of problem for problem. For someone who can be (or currently is) responsible in their drug use, it is logical to conclude that they would prefer the legal route. We just disgaree on whether legalization is better for society than keeping them illegal. I would suggest that there must be some sort of compromise to keep the non-violent user out of prison.

Circumstantial penalties?

I wonder how easily that could translate to a prosecution/defense...

But, there is one drug that is legal - Alcohol. Why should that be legal and no anything else? (Yeah, I know the BIG ALCOHOL company argument - I'm asking more philosophically)

I've often considered this question, as well.
Realistically, the social stigma around drugs just isn't the same around alcohol. I don't think it has everything to do with "big alcohol" or even the legality. It's just so deeply ingrained in our culture. See this very Lounge for an example - I see caffeine and alcohol smilies, but I sure as heck don't see (or expect to see) syringes, spoons or even pills (those little blue ones sure are yummy, though - IIRC).
Maybe it has to do with the Judeo-Christian idea of wine as a sacrament. If God OKs, it, how can it be bad? Even Noah was a lush.
When I worked for Island, we used to go to parties with the High Times crew. No matter how they tried to project an image of class, they sure weren't Wine Spectator.
When I saw Sideways, I saw a depressed alcoholic protagonist who was feeding his denial with the fancy enthusiast nomenclature. Yet, the popularity of the film led to a run on Pinot. Go figure.

I can't answer that, NA. Why was ephedra just outlawed as a dietary supplement? Something like 150 people died in a year from it. Wow. Scary. Alcohol, I would presume, just might account for a few more deaths.