All I can say with absolute certainty is that if all the alcoholics were potheads, planet Earth would be a moderately better place. A bunch of alcoholics gathered together tend to get rowdy, a bunch of potheads tend to get mellow. Personally I've never seen anyone throw up from smoking too much weed. The fact that it's vastly safer than alcohol doesn't mean it should be legal merely by that virtue; the fact that the government deems alcohol use a freedom which we are allowed sets an immutable precedent that use of marijuana is no crime. There's such a thing as civil disobediance.