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On War as Law and Law as War


A locus classicus of international law, the study of the regulation of the legality of the use of force has an unavoidable ring of tragic fanciness about it. War, as acknowledged by David Kennedy in the very first sentence of his book, is indeed ‘a profound topic – like truth, love, death or the divine’. A Pandora's box of multiple distilled intellectual emotions behind which lurk the horrid memories of its survivors, war only truly breathes in the mirrors of the mutilated, in the eyes of the tortured, in the memories of the displaced, in withering flowers over graves crowned, most of the time, by religious symbols. A vague intellectual scent of it, a sort of aseptic intellectual variant, still remains, nonetheless, a field of professional interest for international lawyers.

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1 The National Security Strategy of the United States of America (2002), available at; The National Security Strategy of the United States of America, (2006) available at

2 The use of the term ‘present danger’ in this context is intended to denote ironically the impact on the field of the use of force of the set of foreign-policy prescriptions advocated in 2000 by a number of highly influential neo-conservative thinkers. See R. Kagan and W. Kristol (eds.), Present Dangers: Crisis and Opportunity in American Foreign and Defense Policy (2000).

3 A. A. Cançado Trindade, ‘The Primacy of International Law over Force’, in M. G. Kohen (ed.), Promoting Justice, Human Rights and Conflict Resolution through International Law. Liber Amicorum Lucius Caflish (2007), 1037, at 1054.

4 T. M. Franck, ‘Is Anything “Left” in International Law?’, (2005) Unbound: Harvard Journal of the Legal Left 59, at 61.

6 N. Berman, ‘Intervention in a Divided World: Axes of Legitimacy’, (2006) 17 EJIL 743.

7 A. Anghie, Imperialism, Sovereignty and the Making of International Law (2004), 291.

8 Escorihuela, A. Lorite, ‘Cultural Relativism the American Way: The Nationalist School of International Law in the United States’, (2005) 5 Global Jurist 1, at 114

9 I. de la Rasilla del Moral, ‘El interregno neoconservador’, preliminary study for R. Kagan and W. Kristol (eds.), Peligros Presentes (2005), 3.

10 D. F. Vagts, ‘Hegemonic International Law’ (2001) 95 AJIL 843, at 884.

11 Lorite, supra note 8.

12 For the use of this terminology to refer respectively to ‘foreign affairs law’ and ‘foreign policy’, see ibid.

13 J. C. Yoo, The Powers of War and Peace (2005).

14 Yoo, J. C. and Ho, J. C., ‘The Status of Terrorists’, (2003–4) 44 Virginia Journal of International Law 207.

15 J. C. Yoo, ‘International Law and the War in Iraq’, (2003) 97 AJIL 563, at 564.

16 R. Wedgwood, ‘The Multinational Action in Iraq and International law’, in A. Thakur and W. Pal Singh Sidhu (eds.), The Iraq Crisis and World Order: Structural, Institutional and Normative Challenges (2006), 420.

17 See Yoo, supra note 13.

18 See Yoo and Ho, supra note 14, at 207–15.

19 Glennon, M., ‘Platonism, Adaptivism, and Illusion in UN Reform’, (2006) 6 Chicago Journal of International Law 613.

20 T. M. Franck, ‘Terrorism and the Right to Self-Defence’, (2001) 95 AJIL 839.

21 In Larger Freedom: Towards Development, Security and Human Rights for All, Report of the Secretary-General, UN Doc. A/59/2005 (2005).

22 A More Secure World: Our Shared Responsibility, Report of the High-Level Panel on Threats, Challenges and Change, UN Doc. A/59/565 (2004).

23 J. C. Yoo, ‘Using Force’, (2004) 71 University of Chicago Law Review 729, at 797.

24 Yoo, J. C., ‘Force Rules: UN Reform and Intervention’, (2005–6) 6 Chicago Journal of International Law 641, at 649.

25 Ibid., at 642.

26 A. M. Slaughter, ‘Security, Solidarity and Sovereignty: The Grand Themes of UN Reform, (2005) 99 AJIL 619.

27 See Yoo, supra note 13, at 661.

28 T. M. Franck, ‘The Power of Legitimacy and the Legitimacy of Power in an Age of Power Disequilibrium’, (2006) 100 AJIL 88, at 99.

29 Ibid., at 100.

30 Ibid., at 101.

31 Orakhelashvili, A., ‘Legal Stability and Claims of Change: The International Court's Treatment of Ius ad Bellum and Ius in Bello’, (2006) 75 Nordic Journal of International Law 371.

32 Consequences of the Construction of a Wall in the Occupied Palestinian Territory, Advisory Opinion of 9 July 2004, [2004] ICJ Rep. 136, para. 33 (Judge Higgins, Separate Opinion).

33 Ibid., para. 139.

34 For a defence, see I. Scobbie, ‘Words My Mother Never Taught Me: In Defence of the International Court’, (2005) 99 AJIL 76.

35 Armed Activities on the Territory of the Congo (Democratic Republic of the Congo v. Uganda), Judgment of 19 December 2005, paras. 146–147 (not yet published).

36 Application of the Convention on the Prevention and Punishment of the Crime of Genocide (Bosnia and Herzegovina v. Serbia and Montenegro), Judgment of 26 February 2007, para 406 (not yet published).

37 Armed Activities, supra note 35, paras.146–147.

38 Ibid., at para. 143.

39 Ibid., at para. 143.

40 Orakhelashvili, supra note 31, at 375.

41 Armed Activities, supra note 35 (Judge Simma, Separate Opinion, para. 11). For a doctrinal defence of this position see Tams, C. J., ‘Note Analytique – Swimming with the Tide or Seeking to Stem it? Recent ICJ Rulings on the Law of Self-Defence’, (2005) 18 Revue québécoise de droit international 275.

42 Cançado Trindade, supra note 3, at 1054.

43 I. Kant, Die Metaphysik der Sitten, in I. Kant, Kants Werke (1968), 355.

44 H. Lauterpacht, The Function of Law in the International Community (1933), 64.

45 ‘[The Leviathan] hath the use of so much power and strength conferred on him, that by terror thereof, he is enabled to perform the wills of them all, to peace at home, and mutual aid against their enemies abroad’. T. Hobbes, Leviathan, in T. Hobbes, The English Works of Thomas Hobbes of Malmesbury, ed. W. Molesworth (1966), III, at 158.

46 Quoted by T. Couture, ‘State’, in C. B. Gray (ed.), The Philosophy of Law: An Encyclopedia (1999), II, at 836.

47 ‘The object of government is the suppression of such violence as might . . . bring into jeopardy the well being of the community or its members; and the means it employs are constraint and violence of a more regulated kind’. W. Godwin, An Enquiry Concerning Political Justice (1976).

48 ‘Ist das Recht aber – rein positivistisch betrachtet – nichts anderes als eine äussere Zwangsordnung, dann wird es nur als eine spezifische soziale Technik begriffen: der erwünschte soziale Zustand wird dadurch herbeigeführt, dass an das menschliche Verhalten, das das kontradiktorische Gegenteil dieses Zustandes bedeutet, ein Zwangsakt (das ist, die zwangsweise Entziehung eines Gutes: Leben, Freiheit, wirtschaftlicher Wert) als Folge geknüpft wird’. H. Kelsen, Reine Rechtslehre: Einleitung in die rechtswissenschaftliche Problematik (1934), 28–9.

49 ‘Ein Gezetz in diesem gesetzlosen Zustande zu denken, ohne sich selbst zu widersprechen’. Kant supra note 43, at 347.

50 This author dates the origin of these Latin labels at around 1930. R. Kolb, ‘Origin of the Twin Terms Jus ad Bellum/Jus in Bello’, (1997) International Review of the Red Cross 553. The expression jus belli is, of course, centuries old, as shown, for example, by the titles of the works of Francisco de Vitoria, Relectio de iure belli (1539), and Hugo Grotius, De iure belli ac pacis (1625).

51 ‘[T]he relatively recent coinage of Latin phrases to describe these fields of law and the more recent renaming of jus in bello as “international humanitarian law” appear to reflect a persistent discomfort about the semantic conjunction of law and war.’ Berman, N., ‘Privileging Combat? Contemporary Conflict and the Legal Construction of War’, (2004–5) 43 Columbia Journal of Transnational Law 1.

52 ‘As an international lawyer, I trained to be a professional outsider to warfare. . . . When I studied history and political science, war and peace seemed utterly distinct: “Make peace, not war” was the slogan.’

53 As was also noted by Nathaniel Berman. ‘[L]aw's role in relation to war is primarily not one of opposition but of construction – the facilitation of war through the establishment of a separate legal sphere immunizing some organized violence from normal legal sanction.’ See Berman, supra note 51, at 1. ‘I argue that it is misleading to see law's relationship to war as primarily one of the limitation of organized violence. . . . Rather than opposing violence, the legal construction of war serves to channel violence into certain forms of activity engaged in by certain kinds of people, while excluding other forms engaged in by other people.’ Ibid., at 4–5. Kennedy expressly acknowledges Berman's influences on his own work. See Kennedy, Of War and Law, at x.

54 F. J. Contreras and I. de la Rasilla, ‘Humanitarismo crítico y crítica del humanitarismo’, preliminary study for D. Kennedy, El lado oscuro de la virtud, trans. F. J. Contreras and I. de la Rasilla (2007), 11, at 30. See, e.g., ‘I wanted to be in the field, but I wanted to develop and make known an intuition about the field's limits and dark side that seemed impossible to speak in the disciplinary vocabulary.’ Kennedy, D., ‘Thinking against the Box, (1999–2000) 32 New York University Journal of International Law and Politics 397.

55 Contreras and de la Rasilla, supra note 54, at 28.

56 ‘For those of us outside the military who think about law restraining warfare, it is easy to overlook the many war-generative functions of law: the background rules and institutions for buying and selling weaponry, recruiting soldiers, managing armed forces, encouraging technological innovation, making the spoils of war profitable, channelling funds to and from belligerents or organizing public support. The military also turns to law to discipline the troops, to justify, excuse and privilege battlefield violence, to build the institutional and logistical framework from which to launch the spear.’

57 ‘When the United States uses the Security Council to certify lists of terrorists to force seizure of their assets abroad, we might say that they have weaponized the law. . . . Military action has become legal action, just as legal acts have become weapons.’

58 K. Marx, Die deutsche Ideologie, in K. Marx and F. Engels, Werke (1978), III, 33. For an application of Marxian analysis to international law see S. Marks, ‘Big Brother is Bleeping Us – With the Message that Ideology Doesn't Matter’, (2001) 12 EJIL 1, at 109. See also C. Miéville, Between Equal Rights: A Marxist Theory of International Law (2005); and M. Koskenniemi, ‘What Should International Lawyers Learn from Karl Marx?’, (2004) 17 LJIL 229. Further reading would include B. Bowring, ‘Ideology Critique and International Law: Towards a Substantive Account of International Human Rights’, in C. Warbrick and S. Tierney (eds.), Towards an International Legal Community: The Sovereignty of States and the Sovereignty of International Law (2006), 193; and S. Marks (ed.), International Law on the Left: Re-examining Marxist Legacies (2008).

59 T. M. Franck, Recourse to Force: State Action against Threats and Armed Attacks (2002), 3.

60 ‘[T]he acceleration and escalation of means for launching an attack soon confounded the bright line drawn by the law, effecting a reductio ad absurdum that, literally, seems to require a state to await an actual attack on itself before instituting countermeasures. Inevitably, states responded to the new dangers by claiming a right of “anticipatory self-defence”’. Ibid., at 4.

61 Kennedy's approach is here similar to that adopted by Berman. Compare: ‘[T]he forms of this legal construction of war are highly contingent, the subject of historical variation and political contestation’ (Berman, supra note 51, at 1). See also ‘The forms of this legal construction are highly contingent, both in the sense of having varied historically and in the sense of having been contested within each period. Every time jus in bello was renegotiated . . . the scope of the combatants' privilege was hotly contested.’ Ibid., at 6.

62 ‘The notion that a public declaration by a sovereign marks the boundary between war and peace now seems unduly formal and remarkably out of touch with the play of forces within and without sovereign territories that generate interstate violence.’

63 The evolution is correctly summarized by Berman in these terms: ‘[I]ts [ius in bello's] movement from subjective determinations by sovereigns of the existence of war to purportedly objective evaluations of the facts of armed conflicts; from limitations to certain kinds of states to universalization to all states; from exclusion of colonial peoples, whether or not organized into states, to a still-contested expansion to certain oppressed peoples not organized into states; from wholesale exclusion of internal armed conflicts to partial, and also still-contested, inclusion of some of them.’ Berman, supra note 51, at 22.

64 ‘Never before has the applicability of the laws of war been made to turn on the purported aims of a conflict.’ Sofaer, A., ‘Terrorism and the Law, (1986) 64 Foreign Affairs 901.

65 In fact, Kennedy enlarges perhaps too much the range of possible actors, to the point that the boundary between war and ordinary delinquency almost vanishes: ‘[V]iolence has become a tactic for all sorts of players – warlords and drug lords and freelance terrorists and insurgents and religious fanatics and national liberation armies and more. States have lost the monopoly on metaphoric as well as actual warfare.’ Kennedy, Of War and Law, 19.

66 ‘[P]erfidious attacks on our military – from mosques, by insurgents dressing as civilians or using human shields – . . . are very likely to be interpreted by many as reasonable, ‘fair’ responses by a massively outgunned, but legitimate, force. There is no question that technological asymmetry erodes the persuasiveness of the ‘all bound by the same rules’ idea. It should not be surprising that forces with vastly superior arms and intelligence capacity are held to a higher standard in the court of world public opinion than their adversaries.’

67 At least humanitarian international law provides a common arena in which the global conversation about the limits of war legitimacy can unfold: ‘What is striking, however, is the extent to which even enemies who stigmatize one another as not sharing in civilization nevertheless find themselves using a common vocabulary. . . . The common vernacular for these inter- and intra-elite conversations is increasingly provided by law.’ Kennedy, Of War and Law, 24–5.

68 We are of course employing the term ‘realism’ in the sense connoted by the American ‘realist’ tradition of jurisprudential thought (Llewellyn, Pound, etc.); we are not alluding to the political realist tradition of Morgenthau, Herz, and Kennan.

69 Kennedy evokes – with a certain tender self-irony – that conceptual world of sharp boundaries that presided in his youth, in which war was still clearly distinguishable from peace: ‘War, we learned, “broke out” when “disputes” could not be resolved peacefully, when cosmopolitan reason gave way to nationalist passion, when the normal “balance of power” was upset by abnormal statesmen. These bad-guy statesmen pursued outmoded projects of aggrandizement, domination, aggression, or imperialism. They were in cahoots with what we called “the military industrial complex” – not knowing we were quoting Eisenhower.’

70 ‘[T]he strategies of peace continue in war, and vice versa.’

71 Similarly, ‘[a] more important doubt about a traditional law in war came from the loss of confidence that war was, in fact, so sharply distinct from peace.’ Ibid., at 107.

72 ‘Was it war – or was it peace? Looking back, as historians, we could argue either way, for surely the Cold War was both a titanic global struggle and a period of remarkable stability among the great powers.’

73 ‘[T]he nature of war has itself changed. The Second World War – a “total” war, in which the great powers mobilized vast armies and applied the full industrial and economic resources of their nation to the defeat and occupation of enemy states – is no longer the prototype.’

74 According to some analysts, the new “intelligent” weapons enable armies to attack a country in a relatively harmless way, striking its headquarters “surgically” without damaging civilian population and/or civilian infrastructures in an indiscriminate fashion. M. Ignatieff, Virtual War: Kosovo and Beyond (2001).

75 ‘The absolute on/off nature of the 19th-century distinctions – either it was war or it was peace – seemed too rigid to facilitate the more nuanced approach to diplomacy opened up by unbundling sovereignty into a collection of competences, and arranging diplomatic efforts to influence other sovereigns along a continuum from diplomatic suggestion to invasion.’ See also Berman, supra note 51, at 26.

76 M. Veuthey, Guérilla et droit humanitaire (1983), 356.

77 See ibid., at 91.

78 Dworkin's famous doctrine about rules and principles was to a large extent foreshadowed by Roscoe Pound in R. Pound, Justice According to Law (1951).

79 See R. M. Dworkin, Taking Rights Seriously (1977); A Matter of Principle (1983); Law's Empire (1986).

80 Kennedy has recently co-edited and co-presented a comprehensive anthology of American legal thought, including brief introductory essays to the full text of 20 landmark articles since 1890; among these are works by US legal realists such as Holmes, Cardozo, Pound, etc. D. Kennedy and W. Fisher III (eds.), The Canon of American Legal Thought (2006). See, in Spanish, Kennedy, D., ‘Lon L. Fuller y el canon del pensamiento legal estadounidense’, in (2008) 4 Revista Internacional de Pensamiento Político 230.

81 R. M. Dworkin, ‘The Model of Rules I’, in Dworkin, Taking Rights Seriously, supra note 79, at 26.

82 ‘[According to the classical, ‘normativist’ approach] something is legal if it complies with a valid norm. A norm is valid if it was promulgated by the appropriate authority using the authorized procedure. But, in the new law of force, the “model of standards” displaces the “model of rules”. The binding force of a standard depends on its inherent persuasiveness or reasonableness, and not on its pedigree or formal validity: an alternative way of thinking about the status – and enforceability – of norms has developed which emphasizes the persuasiveness, rather than the validity of norms. . . . You might be persuaded because you believe the norm is valid and think you should follow the valid rules. But you might also be persuaded because you think the rule is wise or ethically compelling.’

83 This is also a Dworkinian idea: ‘Rules are applicable in an all-or-nothing fashion. If the facts a rule stipulates are given, then either the rule is valid, in which case the answer it supplies must be accepted, or it is not, in which case it contributes nothing to the decision. . . . But this is not the way . . . principles operate. Even those which look most like rules do not set out legal consequences that follow automatically when the conditions provided are met.’ Dworkin, Taking Rights Seriously, supra note 79, 24–5.

84 Actually, saying that ‘everything is a matter of calculation and proportionality’ does not take us very far, as there do not seem to exist universally accepted ‘units of moral measure’. For every individual decision-maker – let alone for international society as a whole – each of these decisions continues to be a dramatic dilemma: ‘The idea of proportionality – or necessity – encourages a kind of strategy, and ethic, by metaphor: the metaphor of weighing and balancing. [But] I have learned that if you ask a military professional precisely how many civilians you can kill to offset how much risk to one of your men, you won't receive a straight answer.’

85 ‘[U]ltimately, the questions are no different for torture. When, if ever, does it work?’

86 ‘Some commentators reacted to the 1996 International Court of Justice opinion on the legality of the threat or use of nuclear weapons . . . by shaming the court for speaking with nuance about an apocalypse. . . . [But] placing nuclear weapons on the other side of a sharp conceptual boundary from “conventional war” is no different from sharply differentiating war from peace. What happens when the political tactics on the “good” side of the boundary seem worse?’

87 Conflicts are characterized – like the other wars following the Second World War – by ‘the ubiquity of confrontation’ and ‘the interpenetration and reciprocal encirclement’ of the opposing parties. See Veuthey, supra note 76, at 21.

88 ‘Who was the enemy – and where was the battlefield? The old days of industrial warfare are over. . . . The battlespace is at once global and intensely local; there are no front lines. Here at home, we hardly seem at war – the enemy, the conflict, the political goal, all have become slippery.’

89 ‘Something is undeniably lost when an ethically self-confident law is transformed into a strategic discourse.’

90 On a similar note, Berman: ‘Rather than contesting the line between war and not-war, those engaged in such instrumentalization employ the distinction itself for partisan advantage – seeking to achieve practical or discursive gains through shifting back and forth between war and not-war.’ Berman, supra note 51, at 7.

91 ‘[T]he law in war will have winners and losers. Battling in the shadow of the law, some will find their strength multiplied, others will find their available tactics stigmatized.’

92 ‘We have left the world of legal validity behind, except as a claim made to an audience.’

93 See Contreras and de la Rasilla, supra note 54.

94 See, for example, M. Foucault, Surveiller et punir (1975); L'ordre du discours (1971).

95 ‘It seems hard to imagine ambitious and creative people repeatedly transforming their disciplinary vocabulary . . . and faithfully endeavoring to innovate, only to find themselves, in effect, being spoken by their professional vocabularies. It is easy to imagine that there must be some kind of “deep structure” here, guiding the hand of these hapless international lawyers as they repeatedly push for new thinking which turns out to be a rearrangement of their pre-existing ambivalences.’ Kennedy, supra note 54, at 407.

96 Kennedy alludes to ‘the unbundling of the “sovereign power to make war” into a range of public and private competences, shared out among many departments. . . . Many departments of government will be involved, their responsibilities and powers parcelled out by complex administrative arrangements.’ See Kennedy, Of War and Law, at 149. Responsibility for the decision is thus diluted in a variety of planes and instances, giving the impression that it is the state machinery as a whole that gravitates irremediably in a given direction, so that not even the highest authorities exercise a true discretion: ‘We now know that although September 11 opened a window of plausibility for the invasion of Iraq, the campaign had already long been under way – and not simply because the leadership, the Bush family, say, was “obsessed” with Iraq, but also, and more importantly, because an entire administrative machine had been set in motion, with its own timetables and credibility requirements. . . . By the time we focused on “the president deciding”, it is not at all clear how much room to manoeuvre he still had. “The United States” had made a commitment to overthrow Saddam Hussein – a commitment whose political and bureaucratic momentum could not easily have been stopped without incurring all manner of further costs.’

97 M. Koskenniemi, From Apology to Utopia: The Structure of the International Legal Argument (2005), at 616. See further M. Koskenniemi, The Gentle Civiliser of Nations: The Rise and Fall of International Law 1870–1960 (2001), at 501: ‘What a culture of formalism cannot tolerate – the transformation of the formal into a façade for the material in a way that denies the value of the formal as such.’

98 M. Koskenniemi, ‘The Politics of International Law’, (1990) 1 EJIL 4, at 8.

99 Ibid., at 8.

100 ‘Si lo que se consigue es la incapacidad o la impotencia para actuar, entonces la pérdida es terrible: sólo los filósofos pueden permitirse, en sus seminarios, el lujo de no tomar decisiones prácticas; el hombre de la calle, los políticos, los jefes de Estado, no. Y si, por el contrario, de la deconstrucción queremos sacar una línea de conducta o un modo de actuar, entonces brota la contradicción. . . . También el deconstructivista más intrépido, cuando corta las ramas en que está sentado, acaba cayéndose.’ M. Pera, ‘El relativismo, el cristianismo y Occidente’, in M. Pera and J. Ratzinger [Benedict XVI], Sin raíces: Europa, relativismo, cristianismo, Islam, trans. B. Moreno (2006), 26–7.

101 D. Kennedy, The Dark Sides of Virtue: Reassessing International Humanitarianism (2005).

* Francisco J. Contreras is Professor (Catedrático) of Philosophy of Law, Seville University; Ignacio de la Rasilla, LLB (U.C. Madrid), MA (Int. Rels., Geneva), MA cand. (Pol.Phil., Seville), is a Ph.D. candidate (doctoral fellowship recipient 2007/2008) in international law, Graduate Institute of International Studies, Geneva; Research Associate, Department of Philosophy of Law, Universidad Pablo de Olavide, Seville; Associate, Spring 2007, Real Colegio Complutense at Harvard, and visiting researcher, European Law Research Center (Harvard Law School), as Research Fellow of SEJ2006-14556JURI, Spanish Ministry of Education. While they were not always coincidental with the authors' own final assessments on certain specific aspects, the authors want to thank the highly enlightening comments made by an anonymous reviewer from the LJIL. Thanks also go to John D. Haskell.

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