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The Ethics of Arming Rebels

  • James Pattison

Despite the popularity of arming rebels as a foreign policy option, there is very little, if any, detailed engagement with the ethical issues surrounding the practice. There is a growing literature on the ethical issues surrounding civil wars and, more specifically, the conditions for engaging in just rebellion; but the focus of this literature is largely on the question of the justifiability of the rebels themselves in engaging in civil war and their conduct when doing so, rather than the permissibility of the arming of rebels by other agents. It is precisely this issue that I want to address here. Overall, I argue that the process should be generally eschewed. More specifically, this article seeks to establish that arming rebels is generally impermissible and only exceptionally morally permissible (even, as I will argue, when rebels are engaged in unjust wars). The former, far more restrictive claim will be established in the first part of the article. The latter, more permissive claim will be established in the second part of the article.

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1 Corten, Olivier and Koutroulis, Vaios, “The Illegality of Military Support to Rebels in the Libyan War: Aspects of Jus Contra Bellum and Jus in Bello ,” Journal of Conflict & Security Law 18, no. 1 (2013), pp. 5993, at p. 90.

2 BBC, “Who is Supplying Weapons to the Warring Sides in Syria?” BBC News, June 14, 2013.

3 Nick Hopkins, “Syria Conflict: UK Planned To Train and Equip 100,000 Rebels,” BBC Newsnight, July 3, 2014.

4 Patricia Zengerle and David Lawder, “U.S. Congress Approves Arming Syrian Rebels, Funding Government,” Reuters, September 18, 2014.

5 Salehyan, Idean, “The Delegation of War to Rebel Organizations,” Journal of Conflict Resolution 54, no. 3 (2010), pp. 493515, at p. 503.

6 Julien Barnes-Dacey and Daniel Levy, “Syria: The Imperative of De-Escalation,” Policy Brief: European Council on Foreign Relations, ECFR/80, May 2013 (London: European Council of Foreign Relations, 2013), p. 2.

7 As far as I am aware, the only dedicated article on the topic is Manuel Davenport, Saint Thomas and Arming the Contras: The Criterion of Legitimate Authority,” Southwest Philosophy Review 4, no. 2 (1988), pp. 4960 . But even this article focuses on Thomistic defenses of legitimate authority rather than considering the issues surrounding arming rebels in detail. Christensen, James, “Weapons, Security, and Oppression: A Normative Study of International Arms Transfers,” Journal of Political Philosophy 23, no. 1 (2015), pp. 2339 has a brief section (pp. 36–39) on arming rebels, but his general focus is on the ethics of the arms trade.

8 Notable examples include Buchanan, Allen, “The Ethics of Revolution and its Implications for the Ethics of Intervention,” Philosophy & Public Affairs 41, no. 4 (2013), pp. 291323 ; Ned Dobos, Insurrection and Intervention: The Two Faces of Sovereignty (Cambridge: Cambridge University Press, 2012); Cécile Fabre, Cosmopolitan War (Oxford: Oxford University Press, 2012), pp. 130–65; and Michael L. Gross, The Ethics of Insurgency: A Critical Guide to Just Guerrilla Warfare (New York: Cambridge University Press, 2015).

9 This is unless the recognized government collaborates with the occupiers, in which case it could be a war of both liberation and rebellion, such as the U.S. supply of arms to the mujahideen in response to the Soviet invasion of Afghanistan in 1979.

10 For instance, Ted Galen Carpenter, “The U.S. Should be Wary of Arming Syrian Rebels,” US News and World Report, November 1, 2012.

11 See, for instance, May, Larry, “Contingent Pacifism and the Moral Risks of Participation in War,” Public Affairs Quarterly 25, no. 2 (2011), pp. 95112 ; Lazar, Seth, “The Responsibility Dilemma for Killing in War: A Review Essay,” Philosophy & Public Affairs 38, no. 2 (2010), pp. 180213 .

12 I leave aside here the complicating issue of whether liability is a matter of culpability or agential responsibility (or some other measure).

13 For a much more in-depth analysis of the principal-agent problem in regard to proxy war, see Salehyan, “The Delegation of War.”

14 Thus, even though I will claim below that the possibility of a stalemate might potentially be a reason to arm unjust rebels, there is a notable countervailing concern—that arming rebels will lengthen and intensify the conflict.

15 Sislin, John and Pearson, Frederic, “Arms and Escalation in Ethnic Conflicts: The Case of Sri Lanka,” International Studies Perspectives 7, no. 2 (2006), pp. 137–58. Sislin and Pearson also find that arms acquisitions correlate “with subsequent escalation,” although they note that there are some variations in degrees of escalation, which might be explained by differences in the weapons being supplied, as well as other factors. They also note that some arms races “might actually be beneficial to the termination of an ethnic war,” since situations when neither a government nor rebel group can win or lose may be “particularly conducive to producing favorable negotiations,” p. 143. This is similar to the point I make below about supplying arms to unjust rebels: just as arming unjust rebels may lead to a stalemate and so peace, so might arms races and escalation. Although such exceptions are rare, arms races and escalation are not necessarily bad, even if generally they will be.

16 Moore, Matthew, “Selling to Both Sides: The Effects of Major Conventional Weapons Transfers on Civil War Severity and Duration,” International Interactions 38, no. 3 (2012), pp. 325–47.

17 I use the term “interceding” agency (rather than the more common term, “intervening agency”) in order not to confuse the issue with other issues in the ethics of military intervention discussed in this article.

18 Dobos, Ned, “International Rescue and Mediated Consequences,” Ethics & International Affairs 26, no. 3 (2012), pp. 335–53.

19 Dobos, “International Rescue and Mediated Consequences,” p. 339.

20 For a similar view, see McMahan, Jeff, “Proportionate Defense,” Journal of Transnational Law and Policy 23 (2014), pp. 136 . The view that interceding agency matters somewhat is, I think, the predominant position in recent just war theory. See, for instance, Hurka, Thomas, “Proportionality in the Morality of War,” Philosophy & Public Affairs 33, no. 1 (2005), pp. 3466, at pp. 47–50.

21 For instance, it was reported that airdrops of arms meant for Kurdish fighters near Kobani were obtained instead by the ISIS rebels that they were fighting. Ewen MacAskill and Martin Chulov, “ISIS Apparently Takes Control of U.S. Weapons Airdrop Intended for Kurds,” Guardian, October 22, 2014.

22 See, further, Hartung, William D., “The New Business of War: Small Arms and the Proliferation of Conflict,” Ethics & International Affairs 15, no. 1 (2001), pp. 7996 .

23 Note that the Diffusion Objection is broader than the concern that the rebels’ war may change to be unjust and the weapons cannot be easily retracted if it does (this is the central objection to arming rebels posed by Christensen in “Weapons, Security, and Oppression,” pp. 37–39). The Diffusion Objection, by contrast, asserts that, even if the justifiability of the rebels’ war does not change, there is still reason to worry about the diffusion of weapons.

24 Again, the intervening agency of others may be thought to reduce some of the wrongness of supplying arms if the diffusion is largely the fault of other actors.

25 This claim is corroborated, interestingly, by the CIA, which in a recent, classified study (seemingly requested by Barack Obama) found that supplying arms to arm and train rebel groups “rarely works.” Mark Mazzetti, “C.I.A. Study of Covert Aid Fueled Skepticism About Helping Syrian Rebels,” New York Times, October 14, 2014.

26 Moore, “Selling to Both Sides,” pp. 335–36.

27 Jackson, Thomas, “From Under Their Noses: Rebel Groups’ Arms Acquisition and the Importance of Leakages from States Stockpiles,” International Studies Perspectives 11, no. 2 (2010), pp. 131–47.

28 See, for instance, Michael Walzer on counterintervention in Just and Unjust Wars, Fourth Edition (New York: Basic Books, 2006), pp. 96–101.

29 See, for instance, the case of the Revolutionary United Front (RUF), which reportedly obtained arms from the ECOMOG troops as ECOMOG lost battles, were subject to ambushes, and even allegedly sold their weapons to the rebels. Berman, Eric G., “Arming the Revolutionary United Front,” African Security Review 10, no. 1 (2001), pp. 614, at p. 9.

30 I contrast the case for arming rebels to direct military intervention in more detail in James Pattison, “Should We Send Weapons or Troops? The Ethics of Supplying Arms vs. Military Intervention,” Stockholm Centre for War and Peace, Ethical War Blog, June 2015,

31 More generally, I think that placing a greater justificatory burden on lesser-evil justifications (and adopting a more nuanced account of lesser-evil justifications that accepts distributive concerns) is the most plausible response to the claims noted above that revisionist just war theory leads to contingent pacifism. I make this point in Pattison, James, “The Morality of Sanctions,” Social Philosophy and Policy 32, no. 1 (forthcoming).

32 There are other negative costs associated with arming rebels which add to its likely disproportionality (but which space precludes considering). For instance, rebel groups with foreign sponsorship are more likely to target civilians since they do not require a civilian base for support. See Idean Salehyan, David Siroky, and Wood, Reed M., “External Rebel Sponsorship and Civilian Abuse: A Principal-Agent Analysis of Wartime Atrocities,” International Organization 68, no. 3 (2014), pp. 633–61; Jeremy M. Weinstein, Inside Rebellion: The Politics of Insurgent Violence (New York: Cambridge University Press, 2007); and Wood, Reed M., “From Loss to Looting? Battlefield Costs and Rebel Incentives for Violence,” International Organization 68, no. 4 (2014), pp. 979–99.

33 I delineate this general nonconsequentialist approach to the ethics of war in James Pattison, Humanitarian Intervention and the Responsibility to Protect: Who Should Intervene? (Oxford: Oxford University Press, 2010).

34 To be clear, last resort is not a necessary condition. Elsewhere, I call it a “presumptive” condition since it should be presumed that war (and arming rebels) should be the last resort. James Pattison, “The Ethics of Diplomatic Criticism: The Responsibility to Protect, Just War Theory, and Presumptive Last Resort,” European Journal of International Relations (forthcoming). The presumption does not apply when there is clear evidence that war (or arming rebels) would be consequentially optimal and the least harmful feasible option. The presumption can also be overridden, even if arming rebels is not the least harmful option, if it is likely to be hugely consequentially optimal (i.e., achieve highly beneficial consequences compared to the other options), given that the difference between doing and allowing is not absolute.

35 This view is implied, for instance, in Chris Havemann's brief remarks on applying just war theory to British arms exports in Ethical Business Around the World: Hawks or Doves? The Ethics of U.K. Arms Exports,” Business Ethics 7, no. 4 (1998), pp. 240–44, at p. 243. It is also defended by Christensen in “Weapons, Security, and Oppression,” p. 37.

36 See, for instance, McMahan, Jeff, “The Ethics of Killing in War,” Ethics 114, no. 4 (2004), pp. 693733 , at pp. 713–14.

37 Similarly, Buchanan, in “The Ethics of Revolution” at pp. 314–15, argues that the justifiability of intervention depends on the current situation, rather than on the previous impermissible acts of the revolutionary movement.

38 This seems to apply most clearly to unjust rebels who are fighting against other unjust parties. In particular, it seems most apt when rebels are fighting a somewhat morally problematic war (e.g., a rebellion that is fought for material gain, with very little representation) against parties whose war is even worse (e.g., other rebels who are fighting a brutal war of extermination or a very ruthless, tyrannical state).

39 Moore, “Selling to Both Sides,” at p. 335.

40 Cunningham, David E., Gleditsch, Kristian Skrede, and Salehyan, Idean, “It Takes Two: A Dyadic Analysis of Civil War Duration and Outcome,” Journal of Conflict Resolution 53, no. 4 (2009), pp. 570–97.

41 Moore, “Selling to Both Sides,” p. 335. Although Moore notes this, as I noted above, he generally finds that increasing the provision of major conventional weapons increases the severity of civil wars.

42 See Barnes-Dacey and Levy, who, in “Syria” at p. 3, discuss this argument in more detail. Also see Nigel Biggar, who argues that the Syrian rebels met most of the just war conditions, but were not legitimate. Nevertheless, he calls for “a more even balance of military forces—and therefore increased Arab and Western support of the rebels” so the regime and its supporters “become convinced that military victory over the rebellion is beyond reach and that political compromise is the only way forward.” Biggar, Christian Just War Reasoning and Two Cases of Rebellion: Ireland 1916–1921 and Syria 2011–Present,” Ethics & International Affairs 27, no. 4 (2013), pp. 393400, at pp. 398–99.

43 To be clear, this does not mean that there are no such cases. For instance, although I take no position here (given the contested facts), it might have been all-things-considered permissible for the United States to arm the Croat forces during the Bosnian war, despite Tuđman's unjust war. The arming of the Croat forces may be claimed to have been beneficial overall, despite the forces’ war crimes in Krajina, since it frustrated the Serb attempts to establish a Greater Serbia.

44 Mary Kaldor, New and Old Wars: Organized Violence in a Global Era, Third Edition (Cambridge: Polity Press, 2012).

45 For a critique somewhat along these lines, see Pogge, Thomas, “Poverty and Violence,” Law, Ethics, and Philosophy 1 (2013), pp. 87111 (on Kasper Lippert-Rasmussen's defence of subsistence wars). Also see Shue, Henry, who, in “Making Exceptions,” Journal of Applied Philosophy 26, no. 3 (2009), pp. 307322 , argues against the use of conceivable exceptions in political philosophy. Although I agree with Shue's claims about the need to consider likelihoods, the case that I will present for the relevance of considering feasible exceptions also applies somewhat to the case for using conceivable exceptions (and so partially responds to his critique of using the latter).

46 Similarly, the private military industry has used the exceptional permissibility of the use of private military and security companies in cases of humanitarian crises to legitimize their industry and to help persuade policymakers to privatize their military services. See, further, Leander, Anna and Munster, Rens van, “Private Security Contractors in the Debate about Darfur: Reflecting and Reinforcing Neo-Liberal Governmentality,” International Relations 21, no. 2 (2007), pp. 201216 ; and James Pattison, The Morality of Private War: The Challenge of Private Military and Security Companies (New York: Oxford University Press, 2014), pp. 195–96.

47 I say that exceptions should be “very explicitly” caveated since I think it can be expected that certain readers will overlook nuances and more subtle statements about general applicability.

* An earlier version of this article was presented to audiences in Brittany, Dublin, Frankfurt, Manchester Metropolitan University, the University of Manchester, the University of Oxford, and the University of Sheffield. I would like to thank the participants for their comments and questions. I would also like to thank the anonymous reviewers for Ethics & International Affairs, the journal's editors, Ned Dobos, Toni Erskine, Cécile Fabre, Christopher Finlay, Mark Reiff, Don Scheid, Michael Skerker, and Jean-Baptiste Jeangène Vilmer for their very helpful written comments. This article was written while holding a research fellowship from the Arts and Humanities Research Council (AHRC) for the project, “The Ethics of the Alternatives to War” (AH/L003783/1). I would like to thank the AHRC for their support.

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