If there was concrete evidence that marijuana caused cancer or really anything that was as damaging as most drugs/alcohol/tobacco then im sure it would be used in the commercials instead of the WEED KILLS!!! ridiculous commericals with the kids with guns or running over people in drive thrus. Weed isnt legal because it directly threatens many industries that have large lobbies in this country, mainly alcohol, tobacco, oil, phama, and in the past cotton. Money talks in this country, and that more than any apparant real danger from weed is the reason behind its illegality.
The saddest thing about this set of laws is the ridiculous incarceration of people either possesing, or selling weed. The second saddest thing is the insane ammount of money spent catching, prosectuting, and jailing these people. This is our tax dollars being wasted on an unjust drug war that will never be won anyway.
Dont know if you have checked it out yet but
www.overgrow.com is a good site for lots of related info whiskey.