This seems like the proper place for this discussion.
The reasons it was made illegal in the first place really don't seem to make that much sense, especially since alcohol and tobacco products are still legal. One reason for it's being seen as somethinng criminal that I've always found interesting (and I really don't want to start a whole other debate by saying this) is the racial aspect of those who were more likely to use it when it was originally made illegal. This is from the wikipedia entry on marijuna:
Although cannabis has been used for its psychoactive effects since ancient times, it first became well known in the United States during the jazz music scene of the late 1920s and 1930s. Louis Armstrong became a prominent and life-long devotee. It was popular in the blues scene as well, and eventually became a prominent part of 1960s counterculture.
Cannabis (drug) - Wikipedia, the free encyclopedia
I really don't think it should be illegal because there really is no proof that it's any worse than other, more legal ways of killing one's brain cells. At the same time, I'm still a bit skeptical on how benifical it can really be because I find it hard to believe that any kind of smoke that goes into the lungs can be very good for you.
Oh, and by the way, I sound like a big pothead or something but that's actually not the case. I was a sociology major in college where I basically focused all my studies on criminology-related topics and my senior thesis dealt with American drug laws and the way they are enforced.