The other thing was that the reason nothing ever happens about reversing prohibition is not so much that there is some clever scheme to stop people exploring consciousness, but that there is no political advantage to promoting liberalisation (which, after all, is the politician's motivation for any action) - but there is a huge political disadvantage in that the papers (i.e. Daily Mail et al in UK) will tear you to pieces. The papers just love furthering the idea of the terrifying dangers and threat posed by 'drugs' (ie the unknown) simply because it is the perfect shock/outrage subject which makes joe public buy the paper, get a thrill from reading it, and so buy it again the next day.
So basically, the papers aren't interested in the facts because it is just too good a story to let go of...and the politicians aren't interested in the facts because they're too terrified of the fear & fury that the papers have whipped up being turned on them.