Nearly a decade and a half after 9/11, the study of international politics has yet to address some of the most pressing issues raised by the attacks, most notably the relationships between Al Qaeda's international systemic origins and its international societal effects. This theoretically broad-ranging and empirically far-reaching study addresses that question and others, advancing the study of international politics into new historical settings while providing insights into pressing policy challenges. Looking at actors that depart from established structural and behavioral patterns provides opportunities to examine how those deviations help generate the norms and identities that constitute international society. Systematic examination of the Assassins, Mongols, and Barbary powers provides historical comparison and context to our contemporary struggle, while enriching and deepening our understanding of the systemic forces behind, and societal effects of, these confounding powers.

'Confounding Powers is the rare book that simultaneously illuminates important events in the past, advances core topics in international theory, and sheds light on pressing contemporary problems. Essential reading for anyone interested in general international relations theory and the puzzles of the current global struggle against violent extremism.’

Daniel Deudney - The Johns Hopkins University

‘Loose talk about how novel actors like Al Qaeda or ISIS are altering international politics is commonplace, but the impact on deep understandings of international politics is fleeting. To get a real bead on these questions, you need what William Brenner accomplishes in this important book: careful theorizing checked against serious historical case studies. Confounding Powers is a deep study that will set the terms of debates about when, why, and how dissimilar actors can upend the established states that dominate the international system.’

William C. Wohlforth - Daniel Webster Professor, Dartmouth College, New Hampshire

'[Confounding Powers] raises important questions and provides provocative answers. It should prompt further research about systemic change and the interactions between international society and the diverse political entities and behaviors that constitute it.'

Zachary C. Shirkey Source: Journal of Interdisciplinary History

'… Confounding Powers makes a valuable contribution to the expanding literature on international systems with 'dissimilar' types of actors. It also helps in opening up space for more innovative approaches that will hopefully reach, in truly 'analytically eclectic' fashion, far beyond the constricting bounds of ahistorical structural approaches such as neo-realism.'

Gunther Hellmann Source: Perspectives on Politics

'In this study of actors that deviate from the structural and behavioural norms of global society, including the Assassins, the Mongols, the Barbary powers and al-Qaeda, the author looks at how such actors emerge and their way their behaviour serves in turn to shape the system they have breached.'

Source: Survival: Global Politics and Strategy