Some states have done just that and have decriminalized possession of marijuana. New York chose to pass the Rockefeller Laws ("re-evaluate the penalty" goes in both directions, btw).
Since we have yet to see any drastic changes to the law, we obviously haven't reached that threshold.
(A million? There's about 20 million people who do illegal recreational drugs.)
A million? There's about 20 million people who do illegal recreational drugs.
Can I assume you agree with the notion, then, that it's time to re-evaluate the penalty of the law itself with regard to marijuana on a federal level?