It is a moral question that we are facing. And there is every reason to believe that keeping marihuana illegal is not just immoral, it's deeply, profoundly irrational. From a rational public policy perspective, marihuana prohibition is, to be charitable, unwise. It may very well be the most unwise public policy around. At least, it is difficult to find public policies that cost so much, benefit us so little, and destroy as many lives as marihuana prohibition. Or so I will argue.