Janina Dill

MPhil Cantab, DPhil Oxon

John G. Winant Associate Professor in U.S. Foreign Policy
Professorial Fellow, Nuffield College
Co-Director, Oxford Institute for Ethics, Law and Armed Conflict (ELAC)
International Relations Network
Nuffield College
Office address
Nuffield College, Staircase J, Room 4

Janina Dill is the John G. Winant Associate Professor of U.S. Foreign Policy at the Department of Politics and International Relations (DPIR) of the University of Oxford. She is also a Professorial Fellow at Nuffield College and Co-Director of the Oxford Institute for Ethics, Law, and Armed Conflict (ELAC). 

Her research concerns the role of law and morality in international relations, specifically in war. In one strand of research, she develops legal and philosophical theories about how international law can be an instrument of morality in war, albeit an imperfect one. This work speaks to debates in just war theory and international law. The second strand of Janina Dill’s research seeks to explain how moral and legal norms affect the reality of war. She also studies how normative considerations can shape mass attitudes towards the use of force and the attitudes of conflict-affected populations. Several of her ongoing research projects concern the moral psychology of decision-making in war.  

Her first book, entitled Legitimate Targets? International Law, Social Construction and US Bombing, proposes a constructivist theory of how international law influences the choice of targets of attack in U.S. air warfare. The book tests the theory with three case studies of U.S. air warfare. It further uncovers tensions between a legal and a moral definition of a legitimate target of attack and one guided by strategic considerations alone. The book appeared with Cambridge University Press as part of the series Cambridge Studies in International Relations in 2015.  

In her second book, entitled Law Applicable to Armed Conflict (co-authored with Ziv Bohrer and Helen Duffy), Dill proposes a moral division of labour between human rights and humanitarian law. The contribution examines under what circumstances each body of law better fulfils what she argues are the moral tasks of law. The book appeared in January 2020 with Cambridge University Press. 

Before joining Nuffield, Janina Dill was an Assistant Professor at the Department of International Relations at the London School of Economics and Political Science. Alongside her current appointments, she is a Fellow at the Rothermere American Institute. She holds a DPhil from Oxford, an MPhil from Cambridge, and a B.A. from the Technical University Dresden.  

Professional Responsibilities

Co-Director of the Oxford Institute for Ethics, Law, and Armed Conflict

Previous Posts

She was previously employed as an Assistant Professor of Normative Political Theory at the Department of International Relations of the London School of Economics and Political Science.


  • International law on the use of force, 
  • Just war theory, 
  • U.S. military practices, 
  • Attitudes towards the use of force, 
  • Theories of international law 


  • Ethics of war
  • Laws of war
  • Air warfare


The Development of the International System and Contemporary Debates in International Relations Theory

US Foreign Policy: Processes and Challenges

DPhil in IR Workshop 

Research Design and Methods in International Relations (Normative Theory)

Janina Dill


Law Applicable to Armed Conflict. Cambridge: Cambridge University Press (2020) - Ziv Bohrer, Janina Dill, Helen Dufy

Which law applies to armed conflict? This book investigates the applicability of international humanitarian law and international human rights law to armed conflict situations. The issue is examined by three scholars whose professional, theoretical, and methodological backgrounds and outlooks differ greatly. These multiple perspectives expose the political factors and intellectual styles that influence scholarly approaches and legal answers, and the unique trialogical format encourages its participants to decenter their perspectives. By focussing on the authors' divergence and disagreement, a richer understanding of the law applicable to armed conflict is achieved. The book, firstly, provides a detailed study of the law applicable to armed conflict situations. Secondly, it explores the regimes' interrelation and the legal techniques for their coordination and prevention of potential norm conflicts. Thirdly, the book moves beyond the positive analysis of the law and probes the normative principles that guide the interpretation, application and development of law.

Legitimate Targets? International Law, Social Construction and US BombingCambridge Studies in International Relations, Cambridge: Cambridge University Press (2015)

Based on an innovative constructivist theory of international law the book investigates the effectiveness of international humanitarian law (IHL) in regulating the conduct of hostilities. A comprehensive exegesis of the law defining a legitimate target of attack reveals an unacknowledged controversy among legal and military professionals about the logic according to which belligerents ought to balance humanitarian and military imperatives: the logics of sufficiency or efficiency. Although IHL prescribes the former, increased recourse to IL in US air warfare is constitutive of a legitimate target in accordance with the logic of efficiency. The logic of sufficiency is morally less problematic. Yet, neither logic satisfies contemporary expectations of effective IHL or legitimate warfare. Those expectations demand that hostilities follow a logic of liability, which proves impracticable. The book proposes changes to IHL, but concludes that according to widely shared normative beliefs on the 21st century battlefield there are no truly legitimate targets.

Reviews and Discussions

"A Kettle of Hawks: Public Opinion on the Nuclear Taboo and Non-Combattant Immunity in the United States, United Kingdom, France and Israel," Security Studies, accepted, with Scott D. Sagan and Benjamin A. Valentino 

"Attitudes toward the Use of Force: Instrumental Imperatives, Moral Principles, and International Law," American Journal of Political Science, Vol.63 (3), 2021, pp. 612-633, with Livia I. Schubiger (open access !) 

"Distinction, Necessity, and Proportionality: Afghan Civilians' Attitudes Towards Wartime Harm," Ethics and International Affairs, 2019, Vol. 3 (3), 315-342

"Do Attackers have a Legal Duty of Care? Limits to the 'Individualisation of War'," International Theory, 2019, Vol. 11 (1), 1-25 (open access!)

"The Rights and Obligations of Parties to International Armed Conflicts: From Bilateralism but not Towards Community Interest?" in: Eyal Benvenisti and George Notle (eds.) Community Interests Across International Law (Oxford: Oxford University Press, 2018)  

"Just War Theory in Times of Individual Right," in: Robyn Eckersley and Chris Brown (eds.) The Oxford Handbook of International Political Theory (Oxford: Oxford University Press, 2018)

"Abuse of Law on the 21st Century Battlefield: A Typology of Lawfare," in: Michael L. Gross and Tamar Meisels (eds.) Soft War: The Ethics of Unarmed Conflict (New York: Cambridge University Press, 2017)

"Forcible Alternatives to War: Legitimate Violence in 21st Century International Relations," in: Jens David Ohlin (ed.) Theoretical Boundaries of Armed Conflict and Human Rights (New York: Cambridge University Press, 2016)

“The 21st Century Belligerent’s Trilemma,” European Journal of International Law, 2015, Vol. 26 (1), pp. 83–108 

“Ending Wars: The jus ad bellum Criteria Suspended, Repeated or Adjusted?” introduction to edited symposium, Ethics, 2015, Vol. 125 (April), pp. 627–630

“The Informal Regulation of Drones and the Formal Legal Regulation of War,” contribution to the symposium on: Allen Buchanan and Robert O. Keohane, “Toward a Drone Accountability Regime,” Ethics and International Affairs, 2015, Vol. 29 (1), pp. 51-58

"The American Way of Bombing and International Law: Two Logics of Warfare in Tension," in: Matthew Evangelista and Henry Shue (eds.) Changing Ethical and Legal Norms, From Flying Fortresses to Drones (Ithaca: Cornell University Press, 2014)

“Interpretive Complexity and the Principle of Proportionality,” Proceedings of the Annual Meeting of the American Society of Int. Law, 2014, Vol. 108, pp. 82-105

“Limiting Killing in War: Military Necessity and the St Petersburg Assumption,” Ethics and International Affairs, 2013, Vol. 26 (3), pp. 311-334 – Janina Dill and Henry Shue

“Should International Law Ensure the Moral Acceptability of War?” Leiden Journal of International Law, 2012, Vol. 26 (2), pp. 253-270 

"Puntland's Declaration of Autonomy and Somaliland's Secession: Two Quests for Self-governance in a Failed States," in: Katherine Nobbs and Mark Weller (eds.) Asymmetric Autonomy and the Settlement of Ethnic Conflict (Philadelphia: University of Pennsylvania Press, 2008 & 2010) 

Applying the Principle of Proportionality in Combat Operations,” policy paper for The Oxford Institute for Ethics and Law of Armed Conflict (ELAC), December 2010 

“The Definition of a Legitimate Target of Attack: Not More than a Moral Plea?” Proceedings of Annual Meeting of the American Society of International Law, 2009, Vol. 103, pp. 229-232

“The United States’ Battle with Collateral Damage in Afghanistan,” policy paper for Oxford Analytica – Global Analysis and Advisory, August 2009
“The Principle of Proportionality in the Conduct of War,” policy paper for Oxford Analytica – Global Analysis and Advisory, February 2009

"Staatszerfall als neue Außenpolitische Herausforderung," in: Arne Niemann (ed.) Herausforderungen and die Deutsche und Europäische Außenpolitik - Analysen und Politikempfehlungen (Dresden: TUD Press, 2005) - Janina Dill and Nicolas Lamp

"The DoD Law of War Manual and the False Appeal of Differentiating Types of Civilians,Just Security, December 2016

"Assessing Proportionality: An Unreasonable Demand on the Reasonable Military Commander?" Intercross, EJIL Talk! and Lawfare, October 2016

"Five Don'ts for Introducing a Female Speaker," The Duck of Minerva, reposted on The Times Higher Education, May 2016

"Proportionate Collateral Damage and Why We Should Care What Civilians Think," Just Security, March 2015 

"Inside the Issues 5.7: Legitimate Targets," video pod cast for the Center for International Governance Innovation (GIGI), October 2014

"Israel's Use of Law and Warnings in Gaza," Opinio Juris, July 2014

 "Legitimate Targets? The Partial Effectiveness of International Law in War," pod cast for The Oxford Programme on the Changing Character of War (CCW), March 2013