Humanity isn't ready for it, least not as an over-the-counter "medicine" because we live in a society of over-indulgence. Your average citizen isn't looking for medicine, they're looking for an out from reality, in all honesty the system needs to be fixed before I'll support recreational legalization and many in America feel the same.
I know it might seem kinda asshole-ish to say so but America ain't had a daddy to guide it down a morally-sound path in a long time. Trump's administration is feathering the brakes on progressives for good reason, don't get me wrong I love cannabis as much as the next freedom-loving American but I wanna see it do good in the world, instead of just being another vice or cash crop for the cabal. It's why I trust Sessions' and Trump's stance on the matter.
You're right, no precedent at it's founding or thereafter, yet has it's roots firmly locked in the bible. The People only quote the constitution when they're told no, much like many religious folks only quote scripture in times where they've screwed up. I'm very proud of Q and team for doing what they're doing, they're holding people to a higher standard and instilling a sense of personal responsibility, rather than entitlement. I agree that it should be deregulated eventually, just not yet. Steps.
You know it's not, as do I but people are making the conscious choice to partake of it knowing full-well the possible consequences. Absolving them of personal responsibility is in no way going to do them any favors.