Many doctors are coming to the same conclusion that banning high end recreational drugs has not worked.  Legalizing these substances would eliminate the Cartels and enable th Government to regulate and restrict supply and keep prices high to make them unattractive.

On a mission to legalize coca
http://www.minnpost.com/globalpost/2011/03/29/26970/on_a_mission_to_legalize_coca
By John Otis
LIMA, Peru — Coca leaves can provide a caffeine-like boost. They're made into pasta and cookies. And they're chewed all across the Andes.
But the leaves can also be turned into cocaine, which is why a United Nations treaty calls for the eradication of all coca plants and for an end to the practice of chewing the leaves.
That doesn’t sit well with Bolivian President Evo Morales, a member of the indigenous Aymara group and a former coca grower. Morales claims the U.N. treaty is racist and outdated and is lobbying to remove the provision on coca leaves.

Prevailing, you have enough trouble with your nicotine addiction, the last thing you need is a cocaine addiction on top of it