Antigen, that's a fair and very dificult question. I maintain that there is no authority, not federally. HOWEVER, (wow, that's a big however) things such as drug use, public drunkenness ( public drunkeness is only ever a vice of the poor, the rich have clubs for that sort of thing) Are against the public order. Prostitution as well. Loan-sharking, other crimes. We, that is you and I, if we are to form society, must agree on a set of rules..... and if we are not to become ossified in that society, if we are to be free men and women (that's a nod to you) then we must have social mechanisms which tolerate and encourage the selective breaking of those rules. Hence, religion, yeah, that old time religion which has redemption and forgiveness at it's core. ( i do not count either Communism or Islam as valid religions, for neither has at it's core forgiveness, and both contain war as an essential element. No war, no islam, no communism.) Just a bunch of unruly Sikhs and buddhists and christians and jews and some jains, and first americans ( were they really first? or maybe that's bragging) all of these folk, Hindus and swedes and poles and irish, trading amongst each other and trying hard every day to outwit each other in business, or to see who can have the greenest lawn, or whose car can go faster. Wow, got off on a tangent there,did'nt I.
If the question is strictly limited to drugs,Then here we must be careful. Yes, in my opinion you have the right to use whatever drug you choose, red-rice yeast or nettle or marijuana or whiskey. ( I like whiskey) However, we are fools to believe that drugs can not and are not being used as anti-population weapons. They are.
One of the major problems in america is that we do not think long-term. History to americans is what we had for lunch. Communists think in decades. Other societies have had "drug problems" and they adapted socially. We have yet to. The answer lies, to me, not in public law, which should be very limited, but in private moral law, and that requires a deeper and more far reaching revolution than most are comfortable with. This may be a convoluted argument,so, apologies a'priori. J.O.M And yes, my sense of humour is about that of a ten-year old. ::unhappy::