Myth--

What about DuPont's paper and plastic industries? No, hemp doesn't make the best rope. But it has many, many other uses where its quality meets or excels that of synthetics, and it's much better for the environment besides.

The paper industry in particular stands out to me. Hemp grows quickly and is thus far more renewable than forests. The paper making process is much less toxic (using peroxide instead of chlorine, thereby eliminating dioxin contamination in rivers), it contains significantly less lignin (requiring less sulfer-based chemicals to break down). Hemp, if utilized properly, could probably wipe out the tree-based paper industry, which would have a hugely-positive impact on our environment.

As for your comment about medical marijuana, there are quite a few medical professionals out there who would disagree with you. Are you a medical doctor? Here's a good site that lists all the pros and cons side by side:

Medical Marijuana ProCon.org

Weigh the pros against the cons and draw your own conclusions.