There is too much "money" (debt) to be made by governments and corporations by criminalizing ownership of "illegal" drugs and licensing those very same drugs in different forms to doctors and pharmaceutical companies.

If you think government is ever the answer then you are not looking at things closely.

Stealing from some people (taxes), paying yourself, and then giving whatever you don't want out to some other people if they jump through enough hoops is never going to be a positive thing.