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Table of Contents
List of Contributors
1. Introduction: The Jus Contra Bellum and the Power of Precedent 1 Tom Ruys, Olivier Corten, and Alexandra Hofer
2. The Caroline Incident—1837 5 Michael Wood
PART 1. THE COLD WAR ERA (1945– 89)
3. The Korean War—1950–53 17 Nigel D White
4. The Suez Crisis—1956
Alexandra Hofer
5. The Soviet Intervention in Hungary—1956
Eliav Lieblich
6. The U-2 Incident—1960
Ki- Gab Park
7. The Belgian Intervention in the Congo—1960 and 1964
Robert Kolb
8. The Indian Intervention in Goa—1961
Tom Ruys
9. The Cuban Missile Crisis—1962
Alexander Orakhelashvili
10. The Gulf of Tonkin Incident—1964
Douglas Guilfoyle
11. The US Intervention in the Dominican Republic—1965
Christian Walter
12. The Six Day War—1967
John Quigley
13. The Intervention in Czechoslovakia—1968
Gerhard Hafner
14. The USS Pueblo Incident—1968
Wolff Heintschel von Heinegg
15. The Indian Intervention into (East) Pakistan—1971
Dino Kritsiotis
16. The Yom Kippur War—1973
François Dubuisson and Vaios Koutroulis
17. Turkey’s Intervention in Cyprus—1974
Oliver Dörr
18. The Mayaguez Incident—1975 213 Natalino Ronzitti
19. The Entebbe Raid—1976
Claus Kreβ and Benjamin K Nuβberger
20. The Larnaca Incident—1978
Constantine Antonopoulos
21. The Vietnamese Intervention in Cambodia—1978
Gregory H Fox
22. The Ugandan–Tanzanian War—1978–79
Kenneth Chan
23. Operation Litani—1978
Myra Williamson
24. The Lebanon War—1982
Myra Williamson
25. The Soviet Intervention in Afghanistan—1979–80
Georg Nolte and Janina Barkholdt
26. The US Hostage Rescue Operation in Iran—1980
Mathias Forteau and Alison See Ying Xiu
27. The Iran–Iraq War—1980–88
Andrea de Guttry
28. Israel’s Airstrike Against Iraq’s Osiraq Nuclear Reactor—1981 329 Tom Ruys
29. The US Intervention in Nicaragua—1981–88 342 Jörg Kammerhofer
30. The Falklands/Malvinas War—1982
Etienne Henry
31. South African Incursions into Lesotho—1982
Theresa Reinold
32. The Intervention of the United States and other Eastern Caribbean States in Grenada—1983
Nabil Hajjami
33. The Israeli Raid Against the PLO Headquarters in Tunis—1985 395 Erin Pobjie, Fanny Declercq, and Raphaël van Steenberghe
34. The Killing of Khalil al-Wazir by Israeli Commandos in Tunis—1988 403 Erin Pobjie, Fanny Declercq, and Raphaël van Steenberghe
35. The US Strikes Against Libya—1986
Maurice Kamto
36. The US Intervention in Panama—1989
Nicholas Tsagourias
PART 2. THE POST- COLD WAR ERA (1990– 2000)
37. The ECOWAS Intervention in Liberia—1990–97
Ugo Villani
38. The Gulf War—1990–91
Erika de Wet
39. Intervention in Iraq’s Kurdish Region and the Creation of the No-Fly Zones in Northern and Southern Iraq—1991–2003 469 Tarcisio Gazzini
40. The Intervention in Somalia—1992–95 482
Terry D Gill and Kinga Tibori-Szabó
41. The Intervention in Bosnia and Herzegovina—1992–95 495
Pierre Klein
42. The US Airstrike Against the Iraqi Intelligence Headquarters—1993 504
Paulina Starski
43. The ECOWAS Intervention in Sierra Leone—1997–99 527
Susan Breau
44. The US Strikes in Sudan and Afghanistan—1998 541 Enzo Cannizzaro and Aurora Rasi
45. The Eritrean–Ethiopian War—1998–2000 552 Sean D Murphy
46. The Great African War and the Intervention by Uganda and Rwanda in the Democratic Republic of Congo—1998–2003 575 James A Green
47. The Kosovo Crisis—1999 594
Daniel Franchini and Antonios Tzanakopoulos
PART 3. THE POST 9/ 11- ERA (2001– )
48. The Intervention in Afghanistan—2001– 625 Michael Byers
49. The Iraq War—2003 639 Marc Weller
50. Israeli Airstrikes in Syria—2003 and 2007 662 Lindsay Moir
51. The Israeli Intervention in Lebanon—2006 673 Christian J Tams and Wenke Br ückner
52. The Turkish Intervention Against the PKK in Northern Iraq—2007– 08 689 Kimberley N Trapp
53. ‘Operation Phoenix’, the Colombian Raid Against the FARC in Ecuador—2008 702 Mónica Pinto and Marcos Kotlik
54. The Conflict in Georgia—2008 712 Christine Gray
55. Israeli Military Operations Against Gaza: Operation Cast Lead (2008– 09), Operation Pillar of Defence (2012), and Operation Protective Edge (2014) 729 Christian Henderson
56. The NATO Intervention in Libya—2011 749 Ashley Deeks
57. US Extra-Territorial Actions Against Individuals: Bin Laden, Al Awlaki, and Abu Khattalah—2011 and 2014 760 David Kretzmer
58. The Intervention in Côte d’Ivoire—2011 783
Dire Tladi
59. The Intervention of the Gulf Cooperation Council in Bahrain—2011 795
Agatha Verdebout
60. The Ethiopian Military Intervention in Somalia—2011 803
Jean- Christophe Martin
61. The Intervention of France and African Countries in Mali—2013 812
Karine Bannelier and Theodore Christakis
62. Threats of and Actual Military Strikes Against Syria 2013 and 2017 828
Anne Lagerwall
63. The Crisis in Ukraine—2014 855
Mary Ellen O’Connell
64. The Military Operations Against the ‘Islamic State’ (ISIL or Da’esh)—2014 873
Olivier Corten
65. The Saudi-led Military Intervention in Yemen’s Civil War—2015 899
Luca Ferro and Tom Ruys
66. The ECOWAS Intervention in The Gambia—2016 912 Mohamed S. Helal
List of Contributors
Constantine Antonopoulos Associate Professor of Public International Law, Faculty of Law, Democritus University of Thrace.
Karine Bannelier Associate Professor of International Law, CESICE, University Grenoble Alpes.
Janina Barkholdt PhD candidate, Humboldt University Berlin.
Susan C Breau Head of School and Professor of International Law, University of Reading.
Wenke Brückner PhD Candidate, Institute for International Peace and Security Law, Cologne.
Mchael Byers Professor and Canada Research Chair in Global Politics and International Law, University of British Columbia.
Enzo Cannizzaro Full Professor of International Law and European Union Law, Sapienza University of Rome.
Kenneth Chan PhD (KU Leuven). Postdoctoral research fellow with the Berlin Research Group “The International Rule of Law – Rise or Decline?”, Humboldt University Berlin and University of Potsdam.
Theodore Christakis Professor of International Law, CESICE, University Grenoble Alpes, Member of the Institut Universitaire de France (IUF).
Olivier Corten Professor, Université libre de Bruxelles, Centre de droit international.
Andrea de Guttry Full Professor of Public International Law, Scuola Superiore Sant’Anna, Pisa, Italy.
Erika de Wet SARChI Professor of International Constitutional Law, University of Pretoria; Honorary Professor, University of Bonn.
Fanny Declercq Assistant, University of Louvain (UCL).
Ashley Deeks Professor of Law, University of Virginia Law School.
Oliver Dörr Professor of Public Law, European Law and Public International Law, Osnabrück University.
François Dubuisson Professor of Public International Law, Centre de droit international, Université libre de Bruxelles.
Luca Ferro PhD Candidate, Department of European, Public and International Law, Ghent University.
Mathias Forteau Professor, University of Paris Nanterre and Former Member of the ILC (2012–16).
Gregory H Fox Professor of Law, Director, Program for International Legal Studies, Wayne State University Law School.
Daniel Franchini PhD Candidate, Lincoln College, University of Oxford.
Tarcisio Gazzini Professor of International Law, School of Law, University of East Anglia.
Terry D Gill Professor, Military Law at the University of Amsterdam and the Netherlands Defence Academy.
Christine Gray Professor of International Law, University of Cambridge, and Fellow of St John’s College.
James A Green Professor of Public International Law, University of Reading.
x Douglas Guilfoyle Professor, Monash University.
Gerhard Hafner Professor, Department of European, International and Comparative Law Faculty, Vienna University.
Nabil Hajjami PhD (Université libre de Bruxelles and Université d’Angers). Lecturer in Law, Université Paris Nanterre.
Wolff Heintschel von Heinegg Chair of Public Law, in particular Public International Law, European Law and Foreign Constitutional Law at the Europa Universität, Frankfurt (Oder), Germany.
Mohamed S. Helal Assistant Professor of Law, Moritz College of Law & Affiliated Faculty, Mershon Center for International Security Studies, Ohio State University.
Christian Henderson Professor of International Law, University of Sussex.
Etienne Henry PhD (Neuchâtel), Early Postdoc. Mobility Fellow, Swiss National Science Foundation, project number 168525; Visiting Fellow, ANU College of Law, Australian National University.
Alexandra Hofer Doctoral Researcher in Public International Law at Ghent University; Member of Ghent Rolin-Jaequemyns International Law Institute (GRILI).
Jörg Kammerhofer Senior Research Fellow, University of Freiburg.
Maurice Kamto Former Member of the ILC (2011–16).
Pierre Klein Professor, Centre de Droit International, Université libre de Bruxelles.
Robert Kolb Professor of Public International Law, University of Geneva.
Marcos Kotlik PhD candidate, School of Law, University of Buenos Aires and PhD fellow, National Scientific and Technical Research Council of Argentina.
Vaios Koutroulis Professor of Public International Law, Centre de droit international, Université libre de Bruxelles.
Claus Kreß Professor of Public International Law and Criminal Law, Director of the Institute of International Peace and Security Law and Chair for German and International Criminal Law, University of Cologne, Germany.
David Kretzmer Professor Emeritus of international law, Hebrew University of Jerusalem; Professor of Law, Sapir College.
Dino Kritsiotis Professor of Public International Law and Head of the International Humanitarian Law Unit, University of Nottingham.
Anne Lagerwall Associate Professor, Université libre de Bruxelles.
Eliav Lieblich Associate Professor, Buchmann Faculty of Law, Tel Aviv University.
Jean- Christophe Martin Professor LADIE (Laboratoire de Droit International et Européen) EA 7414, Université Côte d’Azur, France.
Lindsay Moir Professor of International Law, Deputy Director of the McCoubrey Centre for International Law, University of Hull.
Sean D Murphy Manatt/Ahn Professor of International Law at the George Washington University Law School in Washington, DC, Member of the ILC (2012–21).
Georg Nolte Professor of Law, Humboldt University Berlin.
Benjamin K Nußberger LLM (Columbia Law School); PhD Candidate, Institute of International Peace and Security Law, University of Cologne.
Mary Ellen O’Connell Robert and Marion Short Professor of Law, University of Notre Dame.
Alexander Orakhelashvili Senior Lecturer, Law School, Birmingham University, United Kingdom.
Ki- Gab Park Professor, Korea University, Seoul.
Mónica Pinto Professor of International Law and of Human Rights, Former Dean of the School of Law (Facultad de Derecho), University of Buenos Aires (Universidad de Buenos Aires).
Erin Pobjie Research fellow and doctoral candidate, Institute for International Peace and Security Law at the University of Cologne.
John Quigley Professor Emeritus, Moritz College of Law, The Ohio State University.
Aurora Rasi Research fellow in International Law and European Union Law, Sapienza University of Rome.
Theresa Reinold PhD (Tuebingen University). Junior professor of Global and Transnational Cooperation Research at the University Duisburg-Essen.
Natalino Ronzitti Emeritus Professor of International Law, LUISS University in Rome, Member of the Institut de Droit International.
Tom Ruys Professor of International Law, Ghent University.
Paulina Starski Dr, LLB, Senior Research Fellow, Max Planck Institute for Comparative Public Law and International Law, Heidelberg and Postdoctoral Research Fellow at Bucerius Law School, Hamburg.
Christian J Tams Professor of International Law, University of Glasgow and Academic Member, Matrix Chambers.
Kinga Tibori-Szabó PhD (University of Amsterdam). Kosovo Specialist Chambers and University of Amsterdam.
Dire Tladi Professor, University of Pretoria. Member of the ILC (2012–17).
Kimberley N Trapp Senior Lecturer in Public International Law, UCL Faculty of Laws.
Nicholas Tsagourias Professor of International Law, University of Sheffield.
Antonios Tzanakopoulos Associate Professor of Public International Law, University of Oxford; Fellow, St Anne’s College, Oxford.
Raphäel van Steenberghe Professor, University of Louvain (ULC), Research Associate, Belgian National Fund for Scientific Research (FNRS).
Agatha Verdebout PhD (ULB). Researcher, Centre de Droit International, Université Libre de Bruxelles (ULB).
Ugo Villani Professor Emeritus, University of Bari.
Christian Walter Professor, Chair of Public International Law and Public Law, LMU Munich.
Marc Weller Professor of International Law and International Constitutional Studies in the University of Cambridge; Director of the Lauterpacht Centre for International Law.
Nigel D White Professor of Public International Law, University of Nottingham, United Kingdom.
Myra Williamson Associate Professor of Law, Kuwait International Law School.
Michael Wood Barrister at 20 Essex Street, London; Member of the UN International Law Commission; Senior Fellow of the Lauterpacht Centre for International Law, University of Cambridge.
Alison See Ying Xiu LLB (London School of Economics) and LLM (International Legal Studies, NYU); Research Assistant at the ILC in 2016.
Introduction: The Jus Contra Bellum and the Power of Precedent
Tom Ruys, Olivier Corten, and Alexandra Hofer
The international law on the use of force, also known under its Latin epithet of jus ad bellum, or, perhaps more accurately, jus contra bellum, is one of the oldest branches of international law. Its emergence is closely intertwined with the birth of international law itself. More than any other domain of international law, it is an area where law and power politics collide. Notwithstanding the International Court of Justice’s bold assertion that there exists ‘general agreement’1 as to what constitutes an ‘armed attack’ for purposes of triggering the right of self-defence, and notwithstanding the reaffirmation in the 2005 World Summit Outcome that the Charter provisions on the use of force ‘are sufficient to address the full range of threats to international peace and security’,2 it is no secret that the interpretation and application of the jus contra bellum has given rise to, and continues to give rise to, fierce debates and disagreement among legal scholars and, more importantly, among states. A closer look at legal doctrine reveals that different views on the interpretation of the rules governing the use of force between states often reflect different underlying methodological approaches (with authors according different weight, for instance, to ‘physical’ or ‘verbal’ state practice).3 In light hereof, some have created labels, seeking to distinguish between ‘restrictionists’ and ‘expansionists’, between ‘bright-liners’ and ‘balancers’, or between ‘purists’ and ‘eclectics’ (sometimes even categorizing scholars accordingly).4 More imperceptibly, when dealing with the law on the use of force, members of the ‘invisible college of international laywers’ often find it difficult to set aside their own values, allegiances, and perceptions of what is ‘fair’ in international relations.5
At the same time, a common thread in legal doctrine is the importance attached to previous precedents to interpret the jus contra bellum. The power of precedent is not limited to legal doctrine, but is also recognized by states themselves, as can be inferred from numerous Security Council debates. Reliance on precedent—understood here as referring not to judicial precedents, but rather to precedents from state practice and their reception at the international level (or, what Michael Reisman would call ‘international
1 Military and Paramilitary Activities in and against Nicaragua (Nicaragua v US) (Merits) [1986] ICJ Rep 1986 14, [195].
2 2005 World Summit Outcome, UNGA Res 60/1 (24 October 2005) UN Doc A/RES/60/1, [79].
3 Further: Olivier Corten, ‘The Controversies Over the Customary Prohibition on the Use of Force: A Methodological Debate’ (2005) 16 European Journal of International Law 803–22; Olivier Corten, ‘Breach and Evolution of Customary International Law on the Use of Force’, in Enzo Cannizzaro and Paolo Palchetti (eds), Customary International Law on the Use of Force: A Methodological Approach (Nijhoff 2005) 119– 44; Tom Ruys, ‘Armed Attack’ and Article 51 of the UN Charter: Evolutions in Customary Law and Practice (Cambridge University Press 2010) 29–52.
4 See, eg, Matthew C Waxman, ‘Regulating Resort to Force: Form and Substance of the UN Charter Regime’ (2013) 24 European Journal of International Law 151– 89; Tom Farer, ‘Can the United States Violently Punish the Assad Regime? Competing Visions (Including that of Anthony D’Amato) of the Applicable International Law’ (2014) 108 American Journal of International Law 701–15. See also the contributions by Kammerhofer, De Hoogh, and van Steenberghe in the Leiden Journal of International Law, Issue (2016) 29:1.
5 Ruys (n 3) 514.
Tom Ruys, Olivier Corten, and Alexandra Hofer
incidents’ 6)—is indeed an important and unavoidable element of the argumentative process from which the jus contra bellum derives its compliance pull. It can have a beneficial effect in that it can contribute to ensuring consistency and to clarifying the precise meaning and scope of the relevant rules, thus resulting in greater legal certainty. Conversely, it also entails evident risks. Precedents have often been interpreted in completely different ways (by scholars or states), and have sometimes been interpreted in ways which substantially depart from the arguments invoked by the intervening states themselves or from the general appraisal of the international community at the time of the events. Such approach may reflect a deliberate methodological approach, in particular a denial of the relevance of ‘verbal’ practice or a rejection of the Nicaragua axiom.7 Yet, it may also result from a lack of awareness of the precise factual circumstances of past incidents or of the concomitant exchanges of claims and counterclaims by the protagonists and other states. On a different note, excessive reliance on certain precedents to the detriment of others risks creating a distorted image. More concretely, it is clear that scholars and states have often tended to focus on cases involving interventions by a small number of western states (particularly the United States) to sketch the contours of the jus contra bellum.
Against this background, the present volume provides a collection of sixty-five case studies pertaining to specific incidents involving the cross-border use of force, all written by experts in the field of jus contra bellum. The incidents have all occurred after the adoption of the UN Charter in 1945, save for the 1837 Caroline incident, which, in light of its omnipresence in legal doctrine and state discourse, could not be ignored. The volume has sought to comprehensively map the important jus contra bellum precedents throughout the Charter era. The cases concerned include both large-scale military interventions involving ground forces, but also more small-scale incidents including hostile encounters between individual military units, targeted killings (eg through air strikes or commando raids), and hostage rescue operations. Moreover, the volume covers both military operations that have been debated at length within the UN Security Council and/or the UN General Assembly, as well as operations that have hardly evoked any international reaction and/or legal scrutiny at all. It addresses military interventions involving both western and non-western states, great powers and smaller states alike. The editors readily acknowledge that the overview is not exhaustive—readers, we fear, will not receive a refund for identifying precedents that are missing. Indeed, as is clear, for instance, from the periodic Digests of State Practice featured in the Journal on the Use of Force in International Law (JUFIL), border incidents and isolated clashes between military units are an aspect of daily life in many regions of the world. It follows that the volume necessarily presents a selection of case studies, albeit one that, we believe, is not arbitary in nature but the result of careful deliberation. Case studies are ordered chronologically, starting with the 1950 Korean War and ending with the 2017 ECOWAS intervention in the Gambia.
Clearly, most of the case studies included in this volume have previously been the subject of scholarly analysis. This is certainly true for well-known cases such as the US intervention in Afghanistan or the 1999 Kosovo crisis, which have given rise to numerous
6 W Michael Reisman, ‘The Incident as a Decisional Unit in International Law’ (1984) 10 Yale Journal of International Law 1–20.
7 Nicaragua (n 1) [186]: ‘If a State acts in a way prima facie incompatible with a recognized rule, but defends it conduct by appealing to exceptions or justifications contained within the rule itself, then whether or not the State’s conduct is in fact justifiable on that basis, the significance of that attitude is to confirm rather than to weaken the rule.’
academic articles in various international law journals, but also for many other, if somewhat less ‘high-profile’, incidents, such as the Belgian operation in Stanleyville, Congo in 1964 or the Ethiopian intervention in Somalia.8 Entire monographs have even been devoted to some cases.9 Furthermore, various monographs exist of course, whether general jus contra bellum handbooks or more thematically focused works, that touch upon a large number of cases within a single volume.10
However, the distinguishing features of the present volume are twofold. First, to the editors’ knowledge, this is the first attempt to systematically bring together the main jus contra bellum precedents since 1945 into a single work of reference,11 including moreover various cases that have largely escaped from academic attention (such as the Turkish intervention in northern Iraq in 2007– 08 or the killing by Israeli commandos of Khalil al-Wazir in Tunis in 1988).
Second, in order to ensure consistency and transparency, and to maximize the value of the volume as a work of reference, all case studies follow a common approach. Specifically, every chapter starts with a brief overview of the factual background and the political context against which the case is set. Subsequently, the chapters detail the exchange of legal arguments and counter-arguments, by identifying the positions taken by the protagonists involved in the cross-border use of force concerned as well as the reactions from third states and international organizations. The third and fourth sections of each chapter are devoted respectively to the appraisal of the legality of the incident/operation concerned, and to an appraisal of the broader implications of the precedent (or lack thereof) for the evolution of the international law on the use of force. As editors, we have tried to steer clear from influencing the substantive analyses of the contributing authors on controversial jus contra bellum issues (issues on which the editors themselves at times hold conflicting views). Yet, we have insisted—perhaps somewhat obsessively—that authors rigidly respect the abovementioned template. Furthermore, as far as the legality assessment is concerned, we have urged the authors to not only provide their personal legal assessment of the case, but to adopt—inasmuch as possible—a broader perspective and to examine how legal doctrine in general has assessed the legality and the broader legal ramifications of each case, while, where appropriate, clearly identifying personal views as such. Thus, while academic articles focusing on specific incidents at times tend to primarily reflect the author’s appraisal of the legality of the intervention concerned, the approach chosen here
8 See, eg, Alain Gérard, ‘L’opération Stanleyville-Paulis devant le parlement belge et les Nations Unies’ (1967) Revue belge de droit international 242; Olivier Corten, ‘La licéité douteuse de l’action militaire de l’Ethiopie en Somalie et ses implication sur l’argument de l’“intervention consentie”’ (2007) 111 Revue générale de droit international public 513.
9 See, eg, John Quigley, The Six-Day War and Israeli Self-Defense (CUP 2013).
10 See, by way of illustration, Christine Gray, International Law and the Use of Force (3rd edn, OUP 2008); Yoram Dinstein, War, Aggression and Self-Defence (5th edn, CUP 2011); Thomas M Franck, Recourse to Force: State Action Against Threats and Armed Attacks (CUP 2002); Olivier Corten, Le droit contre la guerre: L’interdiction du recours à la force en droit international contemporain (2nd edn, Pedone 2014); The Law against War (Hart Publishing 2010); Mary Ellen O’Connell, International Law and the Use of Force, Cases and Materials (2nd edn, Foundation Press 2008); Noam Lubell, Extraterritorial Use of Force against Non-State Actors (OUP 2010); Michael Scholz, Staatliches Selbstverteidigungsrecht gegen terroristische Gewalt (Duncker & Humblot 2006); Christiane Wandscher, Internationaler Terrorismus und Selbstverteidigungsrecht (Duncker & Humblot 2006); Nyamuya Maogoto, Battling Terrorism: Legal Perspectives on the Use of Force and the War on Terror (Ashgate 2005); Kinga J Tibori-Szabó, Anticipatory Action in Self-Defence: Essence and Limits under International Law (TMC Asser Press 2011); Arthur R Kreutzer, Preemptive Self-Defense: Die Bush-Doktrin und das Völkerrecht (M Press 2004); Tom Ruys, ‘Armed Attack’ and Article 51 of the UN Charter (CUP 2010); LinosAlexandre Sicilianos, Les réactions décentralisées à l’illicite: des contre-mesures à la légitime défense (Librairie générale de droit et de jurisprudence 1990).
11 To our knowledge, the only work that shares some resemblance in this respect is Mark Weisburd’s Use of Force: The Practice of States Since World War II (Pennsylvania State University Press 1997).
Tom Ruys, Olivier Corten, and Alexandra Hofer
has sought to ensure that the case studies provide a balanced appraisal of the legality of the incidents (reflecting opposite views where appropriate) and of the precedent’s place and relevance in the realm of the jus contra bellum.
We are deeply grateful to all of the authors for integrating the abovementioned approach into their respective chapters (and apologize for any nuisance caused along the way). We believe it has contributed to largely achieving the stated objective and to establishing the value of this volume as a work of reference for legal scholars, practitioners, and civil servants alike. We can only hope the reader will agree.
2
The Caroline Incident—1837
Michael Wood
I. Facts and Context
Were it not for the ‘public and vainglorious’1 boasting of one Alexander McLeod about his role in the incident, some three years after the event, the world of international law might never have heard of the ‘unfortunate case of the Caroline’ of 1837. It was McLeod’s arrest on charges of murder and arson that rekindled the incident, and led to the matter becoming a legal and political cause célèbre between the British and American Governments. The events culminated in correspondence (section II below) that—in retrospect at least—is widely seen as a starting point for discussion of the customary international law on selfdefence under the jus ad bellum 2 Even a cursory reading of the correspondence indicates that it covers issues that run like a golden thread through many of the studies in the present volume. A reader of the correspondence will note that both sides took what, on the surface at least, seems to have been a remarkably modern and humane approach, even in the heat of great political controversy. The Caroline formula (‘a necessity of self-defence, instant, overwhelming, leaving no choice of means, and no moment for deliberation’) is much quoted today, even while reliance upon it is criticized from all sides. Writings on the incident are extensive and cannot all be referred to here.3
Unlike most of the case studies in this volume, the Caroline incident itself was not a major event—though it must have been quite spectacular, given the vision of the burning vessel as it descended the Niagara Falls (‘a fate which fills the imagination with horror’). The facts are not entirely clear from the correspondence,4 but it seems that at most two
1 Citations in these early paragraphs are taken from the correspondence reproduced in section II below.
2 (1837–38) 26 British and Foreign State Papers (BFSP) 1372–77; (1837–38) 29 BFSP 1126– 42; 30 BFSP 82–99; see also John Bassett Moore, Digest of International Law vol 1, 681.
3 See, among many, R Y Jennings, ‘The Caroline and McLeod Cases’ (1938) 32 American Journal of International Law 82; Jaroslav Žourek, ‘La notion de légitime defense. Aperçu historique et principaux aspects du problème’ Rapport provisoire (1975) 56 Annuaire de l’Institut de Droit International (Session de Wiesbaden) 52; K R Stevens, Border Diplomacy: The Caroline and McLeod Affairs in Anglo-American- Canadian Relations, 1837–1842 (University of Alabama Press 1989); Martin A Rogoff and Edward Collins, ‘The Caroline Incident and the Development of International Law’ (1990) Brooklyn Journal of International Law 493; Abraham Sofaer, ‘On the Necessity of Pre-emption’ (2003) 14 European Journal of International Law 209; Michael C Wood, ‘Nécessité et légitime défense dans la lutte contre le terrorisme: quelle est la pertinence de l’affaire de la Caroline aujourd’hui?’ in Hubert Thierry and Jean-Pierre Quéneudec (eds), Société française pour le droit international, Colloque de Grenoble, La Nécessité en droit international (Pedone 2007); Christopher Greenwood, ‘Caroline, The’ in Rudiger Wolfrum (ed), Max Planck Encyclopedia of Public International Law (2012); Andrew Clapham, Brierly’s Law of Nations (7th edn, OUP 2012) 468–71.
4 The facts, such as they are, are well described by, among others, Jennings (n 3) and Sofaer (n 3). An Ontario Archaeological and Historical Sites Board plaque reads thus: ‘On the night of December 29–30, 1837, some 60 volunteers acting on the orders of Col. Allan Napier MacNab, and commanded by Capt. Andrew Drew, R.N., set out from Chippawa in small boats to capture the American steamer “Caroline”. That vessel, which had been supplying William Lyon Mackenzie’s rebel forces on Navy Island, was moored at Fort Schlosser, N.Y. There she was boarded by Drew’s men, her crew killed or driven ashore, and after an unsuccessful attempt to start the engines, her captors set the ship afire and left her to sink in the Niagara River. This action almost precipitated war between Britain and the United States.’ <http://ontarioplaques.com/Plaques/Plaque_ Niagara59.html>.
persons died on the night of 29/30 December 1837 (Amos Durfee, and a cabin boy, known as ‘little Billy’).
The incident took place in the context of a difficult period in British–American relations, not long after the War of 1812.5 There was an ongoing rebellion in Upper Canada (now Ontario), then a British colony, with some calling (in vain) for it to declare independence from Great Britain and establish a ‘Republic of Canada’. American citizens were aiding and assisting the Canadian rebels with arms and men from the American side of the border. In mid-December 1837, two rebel leaders, McKenzie and Rolfe, held public meetings in Buffalo, New York, seeking men, as well as arms and ammunition which were collected at the Eagle tavern. On 13 December 1837, some of the rebels and recruits established themselves on Navy Island, a small island within Ontario just above the Niagara Falls,6 where they were supplied from the American shore by a small vessel known as The Caroline. On the night of 29/30 December 1837, British– Canadian militia set off to capture The Caroline. Finding that it had left Navy Island they traced it to Schlosser on the American shore, whereupon they disembarked the crew and passengers, killing in the process Amos Durfee and possibly the cabin boy. They then set fire to the vessel, dragged it into the channel of the Niagara River, and cast it loose over the Falls.
Reports of the number of missing and dead were greatly exaggerated, and Amos Durfee’s body was displayed at a tavern in Buffalo, all of which caused ‘great excitement’ and ‘some degree of commotion’. A first exchange of Notes took place between the United States and Great Britain in early January 1838. However, the matter would probably not have been taken further if it had not been for the arrest of Alexander McLeod in New York in 1841. As summarized by Jennings, ‘[i]n 1841 the condition of Anglo-American relations was such that the desultory correspondence must be replaced by a determined effort for a peace settlement if war was to be averted’.7 Lord Ashburton was sent to Washington as special Minister and further and decisive correspondence then took place.
McLeod’s arrest and subsequent trial raised the issue of the immunity for official acts of members of foreign armed forces. The United States was not, however, able to prevent the trial going ahead. Following his acquittal by the jury (which—after just 20 minutes retirement—found he had not been present on the night), McLeod eventually brought a claim against the United States, before a US–UK General Claims Commission, for compensation for the undue period he was detained; the claim was disposed of in 1854–55, when the Umpire found that it had been settled by the two governments in 1841– 42 and was thus outside the jurisdiction of the Commission.8 The UK Government then gave McLeod a substantial annual pension.
II. The Positions of the Main Protagonists and the Reaction of Third States and International Organizations
As Jennings noted in his celebrated article, published in 1938 just 100 years after the event, ‘paradoxically enough, this locus classicus of the law of self-defence, is a case that turned
5 A B Corey, The Crisis of 1830–1842 in Canadian-American Relations (Yale University Press 1941); Howard Jones, To the Webster-Ashburton Treaty: A Study in Anglo-American Relations, 1783–1843 (University of North Carolina Press 1977).
6 In 1945, an ‘international committee’ proposed that the headquarters of the United Nations should be located on Navy Island: see International Committee to promote Navy Island as permanent headquarters for the United Nations, Proposed United Nations Headquarters, Navy Island at Niagara Falls on the International Boundary between Canada and the United States (Baker, Jones, Hausauer, Inc 1945).
7 Jennings (n 3) 88. 8 Jennings (n 3) 96–99.
essentially on the facts’.9 The legal arguments are well set out in advice from the British law officers,10 and especially in correspondence between the two governments,11 which were essentially of the same mind as to the law, so much so that the key ‘Webster formula’ was repeated no less than three times.
It is worth citing at some length the correspondence between US Secretary of State, Daniel Webster, and the British representatives in Washington (resident Minister, Fox, and special Minister, Lord Ashburton, charged with negotiating an agreement on the north-eastern boundary and other outstanding matters, including the Caroline and McLeod cases), so as to appreciate the context in which the Webster formula was used and repeated.
Secretary of State Daniel Webster sent a Note to the British Minister in Washington, Mr Fox, on 24 April 1841. The Note is lengthy, but deserves to be read in full to understand the context of the frequently cited passage (which is highlighted below). The key passages are reproduced here:
The Undersigned has now to signify to Mr Fox that the Government of the United States has not changed the opinion which it has heretofore expressed to Her Majesty’s Government, of the character of the act of destroying the ‘Caroline ’. It does not think that that transaction can be justified by any reasonable application or construction of the right of self-defence under the laws of nations. It is admitted that a just right of self-defence attaches always to nations, as well as to individuals, and is equally necessary for the preservation of both. But the extent of this right is a question to be judged of by the circumstances of each particular case; and when its alleged exercise has led to the commission of hostile acts, within the territory of a power at peace, nothing less than a clear and absolute necessity can afford ground of justification . . .
That on a line of frontier, such as separates the United States from Her Britannic Majesty’s North American Provinces, a line long enough to divide the whole of Europe into halves, irregularities, violences, and conflicts should sometimes occur, equally against the will of both Governments, is certainly easily to be supposed. This may be more possible, perhaps, in regard to the United States, without any reproach to their Government, since their institutions entirely discourage the keeping up of large standing armies in time of peace, and their situation happily exempts them from the necessity of maintaining such expensive and dangerous establishments. All that can be expected, from either Government in these cases, is good faith, a sincere desire to preserve peace and do justice, the use of all proper means of prevention, and, that if offenses cannot, nevertheless, be always prevented, the offenders shall still be justly punished. In all these respects, this Government acknowledges no delinquency in the performance of its duties .
This Government, therefore, not only holds itself above reproach in every thing respecting the preservation of neutrality, the observance of the principle of non-intervention, and the strictest conformity, in these respects, to the rules of international law, but it doubts not that the world will do it the justice to acknowledge that it has set an example, not unfit to be followed by others, and that by its steady legislation on this most important subject, it has done something to promote peace and good neighborhood among Nations, and to advance the civilisation of mankind.
The Undersigned trusts, that when Her Britannic Majesty’s Government shall present the grounds at length, on which they justify the local authorities of Canada, in attacking and destroying the ‘Caroline ’, they will consider, that the laws of the United States are such as the
9 Jennings (n 3) 92. Emphasis in original. 10 Quoted by Jennings (n 3) 87– 88.
11 The correspondence may be found in various publications, including 26 BFSP 1372–77; 29 BFSP 1126–42; 30 BFSP 82–99; J B Moore, Digest of International Law vol 1, 681; Yale Law School, Lillian Goldman Law Library, The Avalon Project, The Caroline, <http://avalon.law.yale.edu/19th_ century/ br-1842d.asp>.
Undersigned has now represented them, and that the Government of the United States has always manifested a sincere disposition to see those laws effectually and impartially administered. If there have been cases in which individuals, justly obnoxious to punishment, have escaped, this is no more than happens in regard to other laws.
Having asserted that the United States could not be reproached any wrongful conduct, Webster went on to address whether the destruction of the Caroline could nonetheless be justified:
Under these circumstances, and under those immediately connected with the transaction itself, it will be for Her Majesty’s Government to show, upon what state of facts, and what rules of national law, the destruction of the ‘Caroline ’ is to be defended. It will be for that Government to show a necessity of self-defence, instant, overwhelming, leaving no choice of means, and no moment for deliberation. It will be for it to show, also, that the local authorities of Canada— even supposing the necessity of the moment authorized them to enter the territories of the United States at all— did nothing unreasonable or excessive; since the act justified by the necessity of self-defence, must be limited by that necessity, and kept clearly within it. It must be shown that admonition or remonstrance to the persons on board the ‘Caroline ’ was impracticable, or would have been unavailing; it must be shown that daylight could not be waited for; that there could be no attempt at discrimination, between the innocent and the guilty; that it would not have been enough to seize and detain the vessel; but that there was a necessity, present and inevitable, for attacking her, in the darkness of the night, while moored to the shore, and while unarmed men were asleep on board, killing some, and wounding others, and then drawing her into the current, above the cataract, setting her on fire, and, careless to know whether there might not be in her the innocent with the guilty, or the living with the dead, committing her to a fate, which fills the imagination with horror. A necessity for all this, the Government of the United States cannot believe to have existed.12
Subsequently, on 27 July 1842, Webster sent a Note to the Special Minister, Lord Ashburton, enclosing a copy of his Note of 24 April 1841. The main paragraph of the Note of 27 July 1842 read as follows:
The act of which the Government of the United States complains is not to be considered as justifiable or unjustifiable, as the question of the lawfulness or unlawfulness of the employment in which the ‘Caroline ’ was engaged may be decided the one way or the other. That act is of itself a wrong, and an offense to the sovereignty and the dignity of the United States, being a violation of their soil and territory—a wrong for which, to this day, no atonement, or even apology, has been made by Her Majesty’s Government. Your Lordship cannot but be aware that self-respect, the consciousness of independence and national equality, and a sensitiveness to whatever may touch the honor of the country—a sensitiveness which this Government will ever feel and ever cultivate—make this a matter of high importance, and I must be allowed to ask for it your Lordship’s grave consideration.
Lord Ashburton responded, the very next day, with a similarly lengthy and carefully drafted Note. Again, only key extracts can be given here:
In the course of our conferences on the several subjects of difference which it was the object of my mission to endeavour to settle, the unfortunate case of the Caroline, with its attendant consequences, could not escape our attention; for although it is not of a description to be susceptible of any settlement by a convention or treaty, yet being connected with the highest
12 For the earlier correspondence dated 5 January and 6 February 1838, see Jennings (n 3) 88.
considerations of national honour and dignity it has given rise at times to deep excitement, so as more than once to endanger the maintenance of peace .
It is so far satisfactory to perceive that we are perfectly agreed as to the general principles of international law applicable to this unfortunate case. Respect for the inviolable character of the territory of independent nations is the most essential foundation of civilization . . .
Every consideration therefore leads us to set as highly as your Government can possibly do this paramount obligation of reciprocal respect for the independent territory of each. But however strong this duty may be it is admitted by all writers, by all Jurists, by the occasional practice of all nations, not excepting your own, that a strong overpowering necessity may arise, when this great principle may and must be suspended. It must be so for the shortest possible period, during the continuance of an admitted overruling necessity, and strictly confined within the narrowest limits imposed by that necessity.
Agreeing therefore on the general principle and on the possible exception to which it is liable, the only question between us is whether this occurrence came within the limits fairly to be assigned to such exception, whether, to use your words, there was ‘that necessity of selfdefence, instant, overwhelming, leaving no choice of means’ which preceded the destruction of the Caroline, while moored to the shore of the United States .
Having expressed approval at the legal standard put forward by his American counterpart, Lord Ashburton nonetheless contested the account of the incident as hinted at by Secretary of State Webster:
I have only further to notice the highly coloured picture drawn in your note of the facts attending the execution of this service. Some importance is attached to the attack having been made in the night and the vessel having been set on fire and floated down the falls of the river, and it is insinuated rather than asserted that there was carelessness as to the lives of the persons on board. The account given by the distinguished officer who commanded the expedition distinctly refutes or satisfactorily explains these assertions. The time of night was purposely selected as most likely to ensure the execution with the least loss of life, and it is expressly stated that, the strength of the current not permitting the vessel to be carried off, and it being necessary to destroy her by fire, she was drawn into the stream for the express purpose of preventing injury to persons or property of the inhabitants at Schlosser . . .
The correspondence concluded with Webster’s Note to Ashburton of 6 August 1842, the relevant part of which reads:
The President sees with pleasure that your Lordship fully admits those great principles of public law, applicable to cases of this kind, which this Government has expressed; and that on your part, as on ours, respect for the inviolable character of the territory of independent States is the most essential foundation of civilization. And while it is admitted, on both sides, that there are exceptions to this rule, he is gratified to find that your Lordship admits that such exceptions must come within the limitations stated and the terms used in a former communication from this Department to the British Plenipotentiary here. Undoubtedly it is just, that while it is admitted that exceptions growing out of the great law of self-defence do exist, those exceptions should be confined to cases in which the ‘necessity of that self-defence is instant, overwhelming, and leaving no choice of means, and no moment for deliberation.’
Understanding these principles alike, the difference between the two Governments is only whether the facts in the case of the ‘Caroline ’ make out a case of such necessity for the purpose of self-defence. Seeing that the transaction is not recent, having happened in the time of one of his predecessors; seeing that your Lordship, in the name of your Government, solemnly declares that no slight or disrespect was intended to the sovereign authority of the United States, seeing that it is acknowledged that, whether justifiable or not, there was yet a violation of the territory of the United States, and that you are instructed to say that your Government
considers that as a most serious occurrence; seeing, finally, that it is now admitted that an explanation and apology for this violation was due at the time, the President is content to receive these acknowledgments and assurances in the conciliatory spirit which marks your Lordship’s letter, and will make this subject, as a complaint of violation of territory, the topic of no further discussion between the two Governments.
It is worth recalling that, at the same time as laying to rest their differences over The Caroline, the two sides reached agreement on the important Webster–Ashburton Treaty, and each regarded the 1842 correspondence as closing the matter.
III. Questions of Legality
As is apparent from the above correspondence, the United States and the United Kingdom agreed on the applicable law as it stood in 1837 (‘we are perfectly agreed as to the general principles of international law applicable to this unfortunate case’),13 and agreed to differ on the facts (‘the topic [was] of no further discussion between the two Governments’).14
At this distance in time, and with limited access to the facts in what was evidently a very heated matter, there is no point in seeking to assess, by the standards of the time, the legality of the British actions on the night of 29/30 December 1837.15
IV. Conclusion: Precedential Value
The Caroline incident continues to be cited as authority in at least three fields of international law: (i) the law of international responsibility, in particular with regard to the invocation of necessity (état de nécessité ) as a circumstance precluding wrongfulness;16 (ii) the law of international immunities, specifically the immunity of members of armed forces;17 and (iii) in the jus ad bellum law of self-defence. It is also of interest for the interpretation of the principles of necessity and proportionality under international humanitarian law,18 and reminds us of the importance of taking account of international humanitarian law whenever there is a use of force.
The present contribution focuses on the jus ad bellum. Among the issues for which the Caroline correspondence is cited are the right of ‘anticipatory’ self-defence; the criterion
13 Lord Ashburton to Webster, 28 July 1842.
14 Webster to Lord Ashburton, 6 August 1842. See Vaughan Lowe, International Law (OUP 2007) 275–76.
15 Though no less an authority than Waldock, writing in 1952, could say that ‘[i]t is commonly accepted today that the proper limits of the pleas of self-defence are correctly stated in the above principles and that, in the particular circumstances, the destruction of the Caroline fell within these principles’. C H M Waldock, ‘The Regulation of the Use of Force by Individual States in International Law’ (1952) 81 Recueil des Cours 463 (emphasis added).
16 Articles on Responsibility of States for Internationally Wrongful Acts (ARSIWA) UN Doc A/RES/56/83, Annex, Art 25; commentary in ILC, Yb 2001 vol II(2), 80.
17 Secretary of State Webster to the US Attorney General, ‘that an individual forming part of a public force, and acting under the authority of his Government, is not to be held answerable as a private trespasser or malefactor, is a principle of public law sanctioned by the usages of all civilized nations’: J B Moore, A Digest of International Law, vol 2 (US Government Printing Office 1906) 25.
18 Such considerations are apparent from the correspondence. Webster’s Note of 24 April 1837 is redolent of international humanitarian law considerations: ‘it must be shown that daylight could not be waited for; that there could be no attempt at discrimination, between the innocent and the guilty; that it would not have been enough to seize and detain the vessel; but that there was a necessity, present and inevitable, for attacking her, in the darkness of the night, while moored to the shore, and while unarmed men were asleep on board, killing some, and wounding others . .’. The British response will be familiar to anyone involved in modern targeting: ‘The time of night was purposely selected as most likely to ensure the execution with the least loss of life . . .’.
of imminence in the event of anticipatory self-defence; the requirements of necessity and proportionality; and self-defence against non-state actors.
Virtually every author writing in the field of self-defence refers to the Caroline incident,19 including in connection with the modern phenomenon of self-defence against non-state actors.20 Webster’s 1841 formula is often the starting point for debate about the right of self-defence under international law. The issues raised include the use of force in self-defence against non-state actors, anticipatory self-defence, and related questions of imminence and necessity. The former does not seem to have been controversial in the case in question. The latter appears to have been central to the dispute, and remains a matter of pressing concern today.21
The Caroline incident, together with the closely related McLeod case, date from 180 years ago. They are chiefly remembered today for short passages in the correspondence between the US Secretary of State, Daniel Webster, and the British representatives in Washington, which are often considered to encapsulate the requirements for self-defence under international law:
Undoubtedly it is just, that while it is admitted that exceptions growing out of the great law of self-defence do exist, those exceptions should be confined to cases in which the ‘necessity of that self-defence is instant, overwhelming, and leaving no choice of means, and no moment for deliberation.’22
The language used by the Americans and British in the early 1840s is at one and the same time familiar (touching upon contemporary notions such as intervention, necessity, and self-defence) and unfamiliar (given the very different legal background almost 200 years ago23). The issues too are strikingly modern. If the words ‘unable or unwilling’ are not used, the notion seems to be implicit in the communications from the British side. That the venerable Caroline incident was considered to be alive and well in the law applicable in 1940 is clear from the judgment of the International Military Tribunal at Nuremberg; the argument that the German invasion of Norway was justified on the ground of self-defence in the face of an imminent Allied landing was rejected by reference to the Caroline criteria.24 That the Caroline survived into the Charter era may be seen inter alia from Waldock’s reliance on it in his seminal Hague lectures from 1952,25 and in the seventh (1952) edition of Oppenheim, volume II.26 The Caroline has also been invoked on
19 Except perhaps in France, where authors seem to prefer to ignore this Anglo-Saxon precedent. A leading French manual, Patrick Daillier, Mathias Forteau, and Alain Pellet, Droit international public (8th edn, LGDJ 2009), contains a single brief reference to the Caroline incident (at [481]), in the context of state responsibility (self-defence as precluding wrongfulness).
20 This can be seen from the many references to the Caroline incident in the present volume, as in other recent collective works such as Marc Weller (ed), The Oxford Handbook of the Use of Force in International Law (OUP 2015). For recent studies, see Institut de Droit International, ‘Tenth Commission, Present Problems of the Use of Armed Force in International Law: A Self-defence’ Resolution 10A (Session de Santiago, 27 October 2007) <http://www.idi-iil.org/app/uploads/2017/06/Roucounas.pdf >; Pemmaraju Sreenivasa Rao, ‘Non-state Actors and Self-defence: A Relook at the UN Charter Article 51’ (2017) Indian Journal of International Law (published online 23 February 2017).
21 ‘Five Country Ministerial and Quintet of Attorneys General Joint Communiqué’ (US Department of Homeland Security, 18 February 2016) included the following: ‘The Attorneys General agreed to continue to discuss the application of the international law requirements for self-defense, including imminence.’ Australia, Canada, New Zealand, UK, USA: US Department of Homeland Security release, <https://www.dhs.gov/news/ 2016/02/18/five-country-ministerial-and-quintet-attorneys-general-joint-communique>.
22 Webster to Ashburton, 6 August 1837.
23 On the important distinction between self-preservation and self-defence, which may not have been clear to the participants in 1841– 42, see Jennings (n 3) 91–92.
24 (1947) 41 American Journal of International Law 205.
25 Waldock (n 16) 462– 64.
26 Hersch Lauterpacht (ed), Oppenheim’s International Law vol II (7th edn, Longmans 1952).
several occasions before the UN Security Council, for example in connection with Israel’s 1981 attack on Iraq’s Osiraq nuclear reactor.27 The memory of the incident seems to have lost none of its force, as may be seen from the UK Attorney General’s January 2017 speech referred to below.28
A heated debate continues among states and writers over the permissibility of anticipatory self-defence in the Charter era. The central question concerns the meaning of Article 51 of the UN Charter and, in particular, the words ‘if an armed attack occurs against a Member of the United Nations’ (in French, ‘ dans le cas où un Membre des Nations Unies est l’objet d’une agression armée’). Within this debate, the Caroline looms large. States and authors differ in their reading of the Webster correspondence and above all in their views of its current significance. Many tend to focus on the actual words used by Webster, and repeated by the British representatives, and indeed on the words used in a short passage read in isolation from the correspondence as a whole. The Caroline formula is too permissive for some, too strict for others.
The Caroline is dismissed as irrelevant by those who reject the right of anticipatory self-defence, irrelevant because the law on the use of force was quite different in 1837 from what it is in the Charter era; and in any event, even if a right of anticipatory self-defence existed under customary international law it could not have survived nor could it override the express language of Article 51.29
Others favour a wider right than anticipatory self-defence in the Caroline sense (preemptive or even preventive self-defence), arguing that Webster’s language never contemplated situations such as those faced in the twenty-first century, with the possibility of weapons of mass destruction falling in the hands of terrorist groups.30
In other respects, many continue to place great weight on the Caroline incident when considering the use of force in exercise of the right of self-defence, relying on Webster’s language to identify the strict conditions for the exercise of the right, particularly a right of anticipatory self-defence.31
In 2001, the International Law Commission opined that:
The ‘Caroline ’ incident of 1837, though frequently referred to as an instance of self-defence, really involved the plea of necessity at a time when the law concerning the use of force had a quite different basis than it now has.32
27 See, eg, UNSC Verbatim Record (15 June 1981) UN Doc S/PV.2282 [15]–[16]; UNSC Verbatim Record (15 June 1981) UN Doc S/PV.2283 [148] (Sierra Leone). See also UNSC Verbatim Record (9 July 1976) UN Doc S/ PV.1939 [115] (Israel with regard to the 1976 Entebbe raid).
28 At n 36 below.
29 Olivier Corten, Le droit contre la guerre (2nd edn, Pedone 2014) 666– 69; Tom Ruys, ‘Armed Attack’ and Article 51 of the UN Charter: Evolutions in Customary Law and Practice (CUP 2010) 255–59. According to Crawford, ‘[r]eference to the period 1837–1842 as the critical date for the customary law said to lie behind the UN Charter is anachronistic and indefensible’: James Crawford, Brownlie’s Principles of Public International Law (8th edn, OUP 2012) 751. (The language is taken over from the previous edition by Brownlie, which contains a virtually identical sentence: Ian Brownlie, Principles of Public International Law (7th edn, OUP 2008) 734.) ‘[R]eliance on [the Caroline] incident is misplaced’: Yoram Dinstein, War, Aggression and Self-Defence (6th edn, CUP 2017) 225.
30 Sofaer (n 3) 219: ‘The historical setting of The Caroline incident makes clear that Webster’s formulation for determining the legality of self-defence was based on his assumption that the attack was unnecessary because the US was both willing and able to satisfy its obligation to prevent and punish attacks from within its borders. On that assumption, Webster reasonably claimed that the British could use force within the US if the need to act was “instant, overwhelming, leaving no choice of means and no moment for deliberation”.’
31 ‘It is generally accepted that the customary requirements are authoritatively formulated in correspondence between the USA and the UK following the British attack on an American ship, the schooner Caroline, in 1837’ in Jan Klabbers, International Law (CUP 2013) 193.
32 Commentary to ARSIWA Article 25 in ILC, Yb 2001 vol II(2), 81 [5]. It will be recalled that Crawford was the ILC’s Special Rapporteur who brought the articles and commentary to a successful conclusion. For a near
Nevertheless, this rather overlooks the fact that the importance of that language lies not so much in its original use as in its frequent re-use as a precedent. In any event, the notion of necessity in the nineteenth century and self-defence today have a lot in common. That both the facts and the law of the Caroline could be seen today as anticipatory self-defence is apparent from the advice given by the British Law Officers in 1839:
the grounds on which we consider the conduct of the British Authorities to be justified, is that it was absolutely necessary as a measure of precaution for the future and not a measure of retaliation for the past. What had been done previously is only important as affording irresistible evidence of what would occur afterwards.33
A key issue at stake in the Caroline incident was the imminence of the attack against which action was taken. If it is accepted that force may be used in self-defence against attacks from non-state armed groups, and if anticipatory self-defence is admitted (which is of course still contested), the question of imminence becomes crucial.
Official statements and declarations by the United States, the United Kingdom, and Australia suggest that, among those that accept the lawfulness of anticipatory self-defence, the imminence criterion is applied more flexibly today, in the face of threats from such non-state armed groups as Da’esh, than in the past in connection with attacks by states. In the case of non-state actors, the planning stages seem to be viewed as closely intertwined with the attacks.
The US, UK, and Australian Governments have recently set out their positions on the law of self-defence in terms that apparently depart from the Webster formula, but which in fact are not so far removed from the spirit of the correspondence when read as a whole. The US position on the two questions, whether anticipatory self-defence is permitted, and, if so, how the criterion of imminence is to be applied in the case of self-defence against non-state armed groups, was set out, by the Obama Administration, in December 2016 in the following terms:
Under the jus ad bellum, a State may use force in the exercise of its inherent right of self-defense not only in response to armed attacks that have already occurred, but also in response to imminent attacks before they occur. When considering whether an armed attack is imminent under the jus ad bellum for purposes of the initial use of force against another State or on its territory, the United States analyzes a variety of factors. These factors include ‘the nature and immediacy of the threat; the probability of an attack; whether the anticipated attack is part of a concerted pattern of continuing armed activity; the likely scale of the attack and the injury, loss, or damage likely to result therefrom in the absence of mitigating action; and the likelihood that there will be other opportunities to undertake effective action in self-defense that may be expected to cause less serious collateral injury, loss, or damage.’ Moreover, ‘the absence of specific evidence of where an attack will take place or of the precise nature of an attack does not preclude a conclusion that an armed attack is imminent for purposes of the exercise of the right of self-defense, provided that there is a reasonable and objective basis for concluding that an armed attack is imminent.’ Finally, as is now increasingly recognized by the international community, the traditional conception of what constitutes an ‘imminent’
contemporaneous reference to necessity not involving a use of force, see the Anglo-Portuguese dispute of 1832, cited by the International Law Commission ibid, at 81 [4] (‘The extent of the necessity, which will justify such an appropriation of Property, of British Subjects, must depend upon the circumstances of the particular case, but it must be imminent and urgent’).
33 Opinion of 25 March 1839: A D McNair (ed), International Law Opinions, vol 2 (CUP 1956) 228. Emphasis in original.
