We investigate how nondemocratic regimes use the military and how this can lead to the emergence of military dictatorships. The elite may build a strong military and make the concessions necessary for the military to behave as their perfect agent, or they may risk the military turning against them. Once transition to democracy takes place, a strong military poses a threat against the nascent democratic regime until it is reformed. We study the role of income inequality and natural resources in the emergence of military dictatorships and show how the national defense role of the military may facilitate democratic consolidation.