"While I'm not saying that all evil in the world is caused by people on drugs, I will say that I've never seen marijuana/hemp/whatever else do anything really positive for a person outside of draining a couple of thousand dollars per year that could be going to something more useful. Whether or not you get high is your own personal choice, but society as a whole should disapprove of it, because it is harmful, unattractive, and ####s up your brain chemistry."

This sort of mindset just begs for someone to make the "slippery slope" argument, which I now shall.

That's a slippery slope. The legality of something or illegality should not and can not in a free nation, be based contingent upon its constructive and positive effect on the community or the person. Rather it should be based on the negative effect to others and the line should be drawn that it correlates to measurable damages significantly more than other legal activities.

Thus vandalism is a crime while not having a paying job is not and should not be a crime. In that same vein, smoking pot should not be a crime. The fact that it does not positively affect your life or your contribution to society in and of itself should not be criteria for its legality. Its still a broad and highly subjective topic, but those are my two cents. Its kinda hard to nail down a definitive definition of what should and should not be legal.