A pathbreaking history of the regulatory foundations of Americas twentiethcentury aerial preeminence.Today the federal government possesses unparalleled authority over the atmosphere of the United States. Yet when the Wright Brothers inaugurated the air age on December 17 1903 the sky was an unregulated frontier. As increasing numbers of aircraft threatened public safety in subsequent decades and World War I accentuated national security concerns about aviation the need for government intervention became increasingly apparent. But where did authority over the airplane reside within Americas federalist system And what should US policy look like for a device that could readily travel over physical barriers and political bordersIn Sovereign Skies Sean Seyer provides a radically new understanding of the origins of American aviation policy in the first decades of the twentieth century. Drawing on the concept of mental models from cognitive science regime theory from political science and extensive archival sources Seyer situates the development spread and institutionalization of a distinct American regulatory idea within its proper international context. He illustrates how a relatively small group of bureaucrats military officers industry leaders and engineers drew upon previous regulatory schemes and international principles in their struggle to define governments relationship to the airplane. In so doing he challenges the current domesticcentered narrative within the literature and delineates the central role of the airplane in the reinterpretation of federal power under the commerce clause. By placing the origins of aviation policy within a broader transnational context Sovereign Skies highlights the influence of global regimes on US policy and demonstrates the need for continued engagement in world affairs. Filling a major gap in the historiography of aviation it will be of interest to readers of aviation diplomatic and legal history as well as regulatory policy and