Even if we were to take a fully free-market approach to these things, banning certain substances could still be seen as a net positive. While some people can live with addiction (that is, function normally or in an acceptable capacity) many cannot, and those who cannot work due to a drug habit become an economic detriment, whether through poor performance in the workplace or through being fired and becoming an economic non-actor, or worse, a criminal looking for drug money because they can't hold down a job.

The only tilt in favor of total liberalization is that the drugs would be much, much cheaper to obtain, but zero income is still zero income, and is economically adverse, and these problems are only multiplied in societies that acknowledge the government's role as a provider of welfare.

Since no man is an island, even under the bleakest of filters that see man only as an economic animal, wilfully damaging your own health is still bad for society as a whole, and their "right" to damage their own health then ends up infringing upon our rights to happiness (through economic success) or property (through the promoted thievery).

Through a left, right, statist, or libertarian perspective, legalizing hard drugs is a bad idea.

Well, I'm all for marijuana because it's an essentially harmless drug (medically beneficial for a lot of people, in fact), and it makes everything fascinating and hilarious, makes food taste incredible and makes video games more immersive. Introspection is easy when high, and it doesn't make you belligerent like some people who drink, you never get angry or violent, just euphoric and empathetic. You can experience almost anything on a deeper level.

There have been some studies that say it's been linked to some sort of brain damage ("drop in IQ") from heavy, sustained use from a young age, but they are inconclusive, and I don't do nearly enough for this to apply to me even if it was true.

As for legal aspects... well prohibition is just ineffective. It plain and simply does not work. I'm sure others will go into/have gone into more depth here, so there's no point in me doing so.

There is so much wrong with this post I do not know where to begin.  It is clear that you have made up your mind and that there will be no convincing you.

We should make it illegal to punch yourself, since its detrimental to society. Or to drive cars- sure some people can live with this addiction (that is function normally or in an acceptable capacity) many cannot. Many endager not only themselves but others as well when they go out onto the road driving, and though not everyone is a bad driver, we should ban cars since they provide a net negative to our society due to wrecklass drivers. 
or how about draino? you know the stuff the cleans out your clogged drains? that stuff is pure posison!!!! Or canned air! you can get high off of that AND its legal! you dont even need to be 16!!!! AND it can kill you. 

You say that other people hurting themselves denies you your right to "economic success" but thats just it, you have NO right to the success of others. You do not even have a right to happiness as you claim, in America at least you have a right to pursue happiness.  You are basically saying that people should not be allowed to do drugs because in your oppinion it would be economically unproductive (all studies show it would actaully boost the economy significantly but thats neither here nor there)  and would make you unhappy. Therefore you think that you are allowed to infringe on others wants and desires (happiness) in the name of preserving your own. 

The hypocrisy is absolutley outstanding. 

Where can I get this shit?

Seriously though, all that does is make you higher, or as high with less green, so what? It's not like you can OD on MJ. It just means you put less bud in your joint or use a pipe or vape which uses less anyway.

Good lord, where is the logic? How do you arrive at the conclusion that hard drugs turn people into a burden on the state? Do you understand that alcohol is a hard drug and that many that consume it are of no detriment to the economy? Why not take into account that drug prohibition is extremely costly to implement and enforce? Why not consider the fact that drug prohibition is completely ineffective at actually preventing drug use? Also, you talk of the individuals obligations to the state but what about the state's obligations to respect my rights and freedoms? Why only focus on the monetary cost of drug use and not the human cost of prohibition?

Legalization largely eliminates the risk of contamination. Also, what are you basing your final statement on because I suspect that you just made it up.

http://robertlindsay.wordpress.com/2009/09/16/does-marijuana-cause-schizophrenia/

"Nevertheless, the evidence seems to be there, and it is quite frightening to look it over. The initial study was an elegant analysis of Swedish military recruits in 1987.

The increased risk was on the order of 4.5 times for those using by age 15, but down to 1.6 times for those using by age 18. The increased risk was decreasing rapidly. Let’s extrapolate to ages 16 and 17: Age 15: 4.5 X. Age 16: 3.7 X Age 17: 2.65 X. Age 18: 1.6 X. At that rate, all increased risk would have evaporated for users who wait until they are age 19 until they start using.

Since the Swedish study, the evidence has piled up. Still, despite the scary and numbing evidence, there is not yet any evidence that cannabis causes schizophrenia de novo. Instead, it appears to be interacting with some already existing risk factor.

This page is a good repository for the numbing evidence on this score.

However, that site has some serious problems.

They are finding increased risk of schizophrenia from everything from “being too introverted and being alone too much”, emigrating to a new country – up to 4X increased risk, having an unpleasant and unstable home life as a child, experience – social adversity – four or more episodes of “abuse” increased risk by 2.7X, living in a city (3X increased risk), especially an inner city (as opposed to the country), or being vulnerable to depression or anxiety."

So basically don't do it excessively (daily or near-daily use over years is how that's usually defined) when you're younger and it's fine. It's actually possibly beneficial to your brain in numerous ways according to the article and its links.

Law Enforcement Against Prohibition

LEAP say no to crime

http://www.youtube.com/watch?v=LayaGk0TMDc&feature=youtube_gdata_player

WEll considering how many drugs out there save peoples lives every day I do not see how anyone can claim they are bad. You said you wanted to generalize and that would include prescription drugs as well as illegal drugs

Many illegal drugs can be harmful but there is one that is safer than beer or tobacco and that is weed. IN fact it doesnt even fit in with most drugs because it is a plant that you simply dry and smoke. Doesnt need to be processed like cocaine and doesnt need to be cooked like meth.

You really might want to rethink your stance on this because asthma meds are drugs and they help many people as does insulin and many many other drugs

Law Enforcement Against Prohibition

LEAP say no to crime

http://www.youtube.com/watch?v=LayaGk0TMDc&feature=youtube_gdata_player