This article positions the prohibition of psychoactive substances as a material means of strengthening States and State power. We argue that the militarized enforcement of prohibition has known outcomes beyond the control of substances, including the creation of cash economies that, firstly, support the smooth flowing of modern global capitalism, and secondly, finance US allied (reactionary) armed groups internationally. Various national contexts are considered, with a special focus on how these trends are developing in the ongoing “war on drugs” in Mexico.