Perpetual War and International Law Enduring Legacies of the War on Terror

Nearly a quarter century after the September 11, 2001 attacks, the U.S.-led war on terror remains a defining force shaping international law, human rights, and global security. While major combat operations in Afghanistan and Iraq have formally ended, the long-anticipated shift from a war paradigm to a law enforcement approach has yet to materialize. Instead, U.S. and allied counterterrorism activities persist worldwide, raising urgent questions about the role of law in enabling and sustaining armed conflict.

Perpetual War and International Law brings together leading experts to confront the enduring legacies of the post-9/11 era and explore viable alternatives to the use of force. The volume traces how legal and policy frameworks have served to legitimize military action, eroding the boundary between war and peace. Contributors challenge prevailing interpretations of international law in an age of endless war and unconventional threats.

Drawing on insights from law, ethics, and security studies, the volume critically examines how legal and normative precedents established during the war on terror continue to shape contemporary conflicts. It offers bold pathways for shifting from a global order rooted in force to one grounded in restraint and the rule of law. Perpetual War and International Law is a vital intervention, inviting readers to reimagine how international law can constrain violence in an increasingly conflict-ridden world.

The Just Security book series from OUP tackles contemporary problems in international law and security that are of interest to a global community of scholars, policymakers, practitioners, and students. With each volume taking a particular thematic focus and gathering leading experts, the series as a whole aims to rigorously and critically reflect on developments in these areas of law, policy, and practice. Each volume will be accompanied by a series of shorter digital pieces in Just Security's online forum at www.justsecurity.org, which tie the discussion to breaking news and headlines.

Brianna Rosen is the Executive Director of the Oxford Programme for Cyber and Technology Policy and a Senior Fellow at Just Security, where she leads the AI and Emerging Technologies Initiative. She previously served for more than a decade in the U.S. government, including at the White House National Security Council and the Office of the Vice President. Her work on national security, emerging technologies, and foreign affairs has appeared in leading publications. Dr. Rosen received her DPhil and MPP from the University of Oxford as a Clarendon Scholar and has received prestigious awards for academic excellence and public service.

Acknowledgements
List of Contributors

I. Introduction
1. Still at War: Law and the Erosion of Restraint, Brianna Rosen

II. Understanding Perpetual War
2. How Law, History, and Culture Enabled Perpetual War, Mary L. Dudziak
3. Endless War as Aimless War, Cheyney Ryan
4. Rethinking the War Paradigm, Andrew Clapham

III. U.S. Perspectives on the War on Terror
5. The “Ghost Budget”: How America Pays for Endless Wars, Linda J. Bilmes
6. Domestic Repercussions of the U.S. War on Terror, Faiza Patel
7. Assessing the Legacy of U.S. Torture in an Era of Geostrategic Competition, Federica D'Alessandra and Alberto J. Mora

IV. Global Perspectives on the War on Terror
8. The War on Terror and the Jus ad Bellum, Sir Michael Wood KCMG, KC
9. Europe's Role in Perpetual War: From Counterpoint to Convergence, Anthony Dworkin
10. Corruption in Conflict: The U.S. Intervention in Afghanistan, Timor Sharan
11. “Nobody Wanted to Hear Us”: Systemic Civilian Harm in Yemen, Priyanka Motaparthy and Radhya al-Mutawakel

V. Legal and Policy Dimensions
12. Filling the Void: Law, Policy, and Morality at War, Adil Ahmad Haque
13. The Vanishing “Tipping Point” and the Problem of Perpetual War, Tess Bridgeman
14. “Legalistic Policymaking” and Counterterrorism Direct Action, Laura A. Dickinson
15. The Rise of “Self-Defense” and the Fall of Constraints on the Use of Force, Oona A. Hathaway

VI. Ending Perpetual War
16. Alternative Approaches to Counterterrorism, Fionnuala Ní Aoláin KC (Hons)
17. Beyond Redress: Rethinking Transitional Justice, Pablo de Greiff
18. Risk and Ending War, Elad Uzan
19. Forever War and the Jus Ex Bello, Tom Dannenbaum
20. How to Finally End America's Forever War, Harold Hongju Koh