This book is about International Relations Theory. It argues that Neo-classical Realism gives a better explanation of world politics than the rest of themes of Realism. In addition, the book attempts to demonstrate this argument in the case shifting Turkish foreign policy after the Syrian crisis in 2011. Therefore, it addresses the real dynamics in which have led Turkey to threat to establish buffer zone in Syria. This includes the systemic constrains that are produced by the international system and the politics of great power, and the domestic politics inside the country, the domestic missile programs debate. Hopefully, you will obtain benefit after enjoy reading.