The first section glances through history coups, dictatorships, political influence and legacy of military institutions in Latin America, as well as the general success of ex-officers in democratic elections. The second section analyzes both the military ideology and the characteristics of its political practice in the past decades, which are based on the monopoly over "national patriotism"; translated into doctrines of national security, control over national intelligence and police forces, the execution of military-civic programs of local development in remote zones and the legal-based immunity. As a third section, a typology over the transition towards democracy: military oversight and impunity. The analysis follows with another typology of military corps exercising power under the democratic electoral regime: Dictators transformed into democrats and ex-guerilla corps into elected presidents. As a last section, an analysis of new security agendas and military missions during the first decade of the XXI century. Military action under the context of war against organized crime, drug dealing and its effect over internal security is emphasized.