I was a heavy pot smoker back in high school and based on my own experiences with it I wouldn't want it freely available but I do admit it is not physically addictive the way alcohol is. It can be very psychologically addictive, at least it was for me. It became a huge crutch and I felt like I had to be high all the time to function. It also messes with your mind quite a lot, especially when you are high all the time. There were moments when I had to ask myself what being sober even felt like anymore. Whoever said you can take a few puffs and not be impaired is right though. The weird mental effects do not really happen at low doses. Perhaps it ought to be legalized for, say, medical reasons, provided there are actually legitimate ones. I know some folks want it to stimulate appetite in chemo patients and to reduce intra-ocular pressure in those with glaucoma.
we don't even know what it does to the mind! it's dangerous and a mortal sin for a reason
There are studies going back to the India Hemp Drugs Commission Report (1894) and the LaGuardia Committee Report (1944), prepared by the New York Academy of Medicine, showing that it is not dangerous. The 1894 report even specifically addressed moral issues and came to the conclusion that moderate use had no effect on the moral character of the user. Excessive use, of course, like that of alcohol, is a different matter.
The fact is, and few know it or want to admit it, that marijuana was basically legal (with regulation) in the US until the repeal of alcohol Prohibition. Harry Anslinger had been head of the 'Federal Prohibition Bureau' and when it became obvious that Prohibition was going to be repealed he successfully lobbied for a Federal narcotics act and the creation of the 'Federal Narcotics Bureau', of which he became the head, so he and his boys could stay in business.
In truth, the whole 'illegalisation' of marijuana was a power grabbing coup by Anslinger and his agency.
I can only say as a former smoker of MaryJane [for about 5 years fairly heavy] that for the first several years I had no more proplems than drinking several drinks, but near the end I would get ridiculously paranoid.
Maybe there are those who get very paranoid from MJ that do not get this way from a couple of drinks, and this paranoia and the hallucinogenic way it affects some minds is reason to consider its illegality.
From my experience I can deal with reality pretty well on 4 or 5 Sierra Nevadas, but I had a hard time doing anything but huddle in someones basement listening to Moody Blues records for several hours after smoking some chocolate thai stick.
I also remember feeling very depressed a lot after smoking it for a year or so and feeling that it was a crutch and I needed it to escape the depressed feeling.
I realize the same thing can happen with alcohol abuse, but this was a different state of mind, almost a clouded perception of life when I was sober and a slowness in reaction time when I was also sober.
A certain sadness that I never felt from alcohol use the night before. It got to be a lot more dangerous for me now that I look back.
Alright, it seems here that everyone is talking about the ABUSE of marijuana. What about MODERATE use?
It seems that all the problems being stated come from people smoking way too much, and often smoking strains of marijuana that are MUCH STRONGER (they contain much more THC) than other strains of marijuana.
Lets say, for instance, it's just "regular" pot. The slang term when I was growing up for regular pot (again, not heavy stuff like the chronic) was "commercial".
So, moderate use of "commercial"... what's so bad about it?

Again, it's only a sin if used gluttonously and to the point of impairing judgement.