This book explores the emergence of an anarchic states-system in the twentieth-century Arab world. Following the collapse of the Ottoman Empire, Arab nationalist movements first considered establishing a unified regional arrangement to take the empire's place and present a common front to outside powers. But over time different Arab leaderships abandoned this project and instead adopted policies characteristic of self-interested, territorially limited states. In his explanation of this phenomenon, the author shifts attention away from older debates about the origins and development of Arab nationalism and analyzes instead how different nationalist leaderships changed the ways that they carried on diplomatic and strategic relations. He situates this shift in the context of influential sociological theories of state formation, while showing how labor movements and other forms of popular mobilization shaped the origins of the regional states-system.