The dissertation explains why similar coup-installed regimes in Egypt (1952), Iran (1921), and Turkey (1923) developed along different political trajectories (authoritarianism, royal absolutism, and democracy, respectively). While most studies of regime change tend to underline popular forces, I demonstrate that these changes cannot be fully comprehended without a grasp of the shifting power balance within the ruling bloc. I argue that these divergent paths were determined by the ensuing power struggle between the military, security, and political institutions. A thorough comparative and historical examination of the critical junctures that marked the path of this unfolding power relation reveals that the ultimate dominance of the security establishment created an authoritarian police state in Egypt; the dominance of the political apparatus in Iran produced a monarchy vulnerable to overthrow from below; and the dominance of the military allowed enough space for a limited yet expanding democracy to develop in Turkey.