This article explores the security and political effects of militia forces that emerged in Mexico in recent years in reaction to violent organized crime, most prominently in the states of Michoacán and Guerrero. Militia forces are not a new phenomenon in the country; in various forms and guises, they permeate the history of Mexico. Often, militia groups have been sponsored by the Mexican state, including as recently as in the 1990s government counterinsurgency efforts against a leftist anti-globalization insurgency, the Zapatista Army of National Liberation (Ejército Zapatista de Liberación Nacional, EZLN). The anti-drug-cartel militias that emerged after 2006, when then Mexican President Felipe Calderón declared a war on the drug cartels, however, emerged either more or less spontaneously or with the sponsorship of powerful politicians and businessmen, not as a state policy. In fact, for a good number of years the Calderón administration and that of his successor President Enrique Peña Nieto ignored them. Eventually, the behavior and visibility of the militia groups forced the government of Mexico to react. Mexico is a middle-power country with a relatively strong economy; it is not a failing state. Nonetheless, the state has been historically weak or absent in large areas, including those where militias are currently strong. Such weakness of territorial presence and its closely related weakness of rule of law are not only a matter of a lack of governance capacity, but fundamentally also of the decisions the Mexican state and elite have made, namely, not providing the resources necessary to boost state presence in indigenous and rural areas, such as to the drug-cartel and militiarife La Tierra Caliente of Michoacán and Guerrero. Consciously or by default, those areas have been relegated to socio-economic marginalization and underdevelopment