If I’m not mistaken, I think the reason while it’s illegal is in the early 20th century William Randolf Hearst spent a fortune demonizing MJ as the paper made from it is vastly superior to that made of wood pulp, and Hearst had invested heavily into paper mills for his newspaper industry. Wood pulp paper is crap, it actually destroys itself with time due to organic acids. Want to know what’s printed on hemp paper? Try the Declaration of Independence and the Constitution. I doubt those documents would still exist if they were printed on wood paper.
One more thing, from a medical standpoint MJ does far less damage to your body than alcohol, and is NOT addictive, so count me in the “make it legal” camp of Piggs.