Next week ministers from around the world gather in Vienna to set international drug policy for the next decade. Like first-world-war generals, many will claim that all that is needed is more of the same. In fact the war on drugs has been a disaster, creating failed states in the developing world even as addiction has flourished in the rich world. By any sensible measure, this 100-year struggle has been illiberal, murderous and pointless. That is why The Economist continues to believe that the least bad policy is to legalise drugs.