¹ See Schmitt, Carl, Der Nomos der Erde im Völkerrecht des Jus Publicum Europaeum, 2nd ed. (Berlin: Duncker & Humblot, 1974, p. 123fGoogle Scholar.

² Oppenheim, Lassa and Lauterpacht, Hersh, International Law: A Treatise, Vol II, 7th ed. (London: Longmans, Green & Co., 1952), p. 203Google Scholar. See also Rousseau, Charles, Droit international public. Tome III (Paris: Sirey, 1979), p. 123Google Scholar.

³ See, for example, Corten, Olivier, The Law Against War: The Prohibition on the Use of Force in Contemporary International Law (Oxford: Hart Publishing, 2010), pp. 126–97Google Scholar.

⁴ Bartelson, Jens, “Double Binds: Sovereignty and the Just War Tradition,” in Kalmo, Hent and Skinner, Quentin, eds., Sovereignty in Fragments: The Past, Present and Future of a Contested Concept (New York: Cambridge University Press, 2014), pp. 81–95, 88Google Scholar.

⁵ Kaldor, Mary, New and Old Wars: Organised Violence in a Global Era (Hoboken, N.J.: John Wiley & Sons, 2013), pp. 11, 29Google Scholar. For an even more futuristic, and scarier, outlook, see Brooker, Paul, Modern Stateless Warfare (Hampshire: Palgrave Macmillan, 2010)CrossRefGoogle Scholar.

⁶ Fabre, Cécile, in her “Cosmopolitanism, Just War Theory and Legitimate Authority,” International Affairs 84, no. 5 (2008), pp. 963–76CrossRefGoogle Scholar, quotes Kaldor three times in an article of fourteen pages. However, revisionist JWT arguments are generally applicable also in a system dominated by states, so the relation should not be exaggerated.

⁷ Cécile Fabre rejects the idea that there is a need for legitimate authority. See Fabre “Cosmopolitanism, Just War Theory and Legitimate Authority.” See also Lang, Anthony F. Jr., “Authority and the Problem of Non-State Actors,” in Heinze, Eric. and Steele, Brent, eds., Ethics, Authority, and War: Non-State Actors and the Just War Tradition (New York: Palgrave Macmillan, 2009), pp. 47–72 CrossRefGoogle Scholar, 54–55. See further the discussion in Frowe, Helen, The Ethics of War and Peace: An Introduction (Abingdon: Routledge, 2011), pp. 29–47 Google Scholar. At any rate, revisionists agree that the legal regulation of warfare may need to “diverge from the moral principles governing the same area of conduct.” See McMahan, Jeff, “War,” in Estlund, David, ed., The Oxford Handbook of Political Philosophy (New York: Oxford University Press, 2012), pp. 298–315, 305Google Scholar.

⁸ Parry, Jonathan, “Just War Theory, Legitimate Authority, and Irregular Belligerency,” Philosophia 43, no. 1 (2015), pp. 175–96CrossRefGoogle Scholar.

⁹ In this article, however, I will not make a comprehensive argument regarding the inconsistency of conceptions of legitimacy. As I will very briefly indicate below, the authority of national liberation movements to use military means is grounded in the fact that they represent peoples with a right of self-determination. The more limited authority of nonstate armed groups to use military means is only based on their qualifications from a military perspective, while the basis for the legitimacy of the state as an authority is more complex—it could be grounded on control of territory and population, representation of the population, or external recognition.

¹⁰ On the terms “tactical” and “strategic level,” see Gill, Terry D. and Fleck, Dieter, The Handbook of the International Law of Military Operations (New York: Oxford University Press, 2010), p. 483Google Scholar.

¹¹ As Bartelson explains, “Although the question of legitimate authority has been of marginal concern in the recent revival of just war theory, it was an absolutely crucial concern to medieval and early-modern scholarship.” Bartelson, “Double Binds,” p. 88.

¹² Aquinas, Thomas, “War, Sedition and Killing,” in Brooks, Thom, ed., The Global Justice Reader (Oxford: Wiley-Blackwell, 2008), p. 469Google Scholar.

¹³ Johnson, James Turner, “Contemporary Just War Thinking: Which Is Worse, to Have Friends or Critics?” Ethics & International Affairs 27, no. 1 (2013), pp. 25–45, 27CrossRefGoogle Scholar.

¹⁴ This was not without significant exceptions, though. Writers like Vattel developed nomenclatures for various stages of civil strife. See Neff, Stephen, War and the Law of Nations: A General History (New York: Cambridge University Press, 2005), p. 254CrossRefGoogle Scholar.

¹⁵ Schmitt, Der Nomos der Erde im Völkerrecht des Jus Publicum Europaeum (1950), p. 128. See also Neff, War and the Law of Nations, pp. 161–62; and Grewe, Wilhelm, Epochen des Völkerrechts, 2nd ed. (Baden-Baden: Nomos, 1988)Google Scholar, p. 623 et seq.

¹⁶ Article 42 of the UN Charter.

¹⁷ This was with an important caveat for the problematic representations that were hostage to the cold war: the two Koreas, the two Vietnams, and the two Germanys as well as the two contending representatives of China, of which the Beijing delegation replaced the Taipei delegation in 1971.

¹⁸ In fact, there has been a lively discussion on right authority for humanitarian intervention: Should it be by states or the United Nations? The work of the International Commission on Intervention and State Sovereignty (ICISS), formed in the wake the Kosovo campaign in 1999, has served as an international reference point. In its report of December 2001, the Commission dealt with three dimensions of what it called the responsibility to protect—to prevent, to react, and to rebuild. The responsibility to react was explicitly framed in just war language. On right authority, the ICISS was explicitly undecided—in fact divided—on whether the decision to intervene and stop ongoing atrocities could be taken only by the Security Council or whether other bodies (such as the General Assembly, a regional organization, or one or more sovereign states) could take that decision. It is to be noted that all of these candidates for legitimate authority are states or have been created by states. See The Responsibility to Protect: Report of the International Commission on Intervention and State Sovereignty (Ottawa: International Development Research Centre, 2001), pp. 32–37 Google ScholarPubMed. The last section is titled “The Question of Authority.”

¹⁹ See, generally, Kolb, Robert, “Origin of the Twin Terms Jus ad Bellum/Jus in Bello ,” International Review of the Red Cross 37, no. 320 (1997), pp. 553–562 CrossRefGoogle Scholar.

²⁰ For example, perhaps the most standard book on the subject, Gray, Christine D., International Law and the Use of Force (New York: Oxford University Press, 2008)Google Scholar, discusses only use of force against nonstate actors, such as terrorist groups. One important exception is Corten, The Law Against War, pp. 126–97. For a good discussion on armed groups, see Daboné, Zakaria, “International Law: Armed Groups in a State-Centric System,” International Review of the Red Cross 93, no. 882 (2011), pp. 395–424 CrossRefGoogle Scholar.

²¹ Corten, The Law Against War, pp. 126–97. Corten emphatically rejects that possibility after a thorough review.

²² “Authority,” Collins Dictionary of Law (2006), retrieved February 10, 2017, legal-dictionary.thefreedictionary.com/authority.

²³ “What is AUTHORITY?” The Law Dictionary Featuring Black's Law Dictionary Free Online Legal Dictionary, 2nd ed., retrieved February 10, 2017, thelawdictionary.org/authority/.

²⁴ “Authority,” in Gerald and Kathleen Hill, The People's Law Dictionary, retrieved February 10, 2017, dictionary.law.com/Default.aspx?typed=authority&type=1.

²⁵ Tom Christiano, “Authority,” in Edward Zalta, ed., Stanford Encyclopedia of Philosophy, Spring 2013 ed. p. 1, retrieved February 10, 2017, plato.stanford.edu/entries/authority/.

²⁶ Johnson, James Turner, “The Right to Use Armed Force: Sovereignty, Responsibility, and the Common Good,” in Lang, Anthony F. Jr., O'Driscoll, Cian, and Williams, John, eds., Just War: Authority, Tradition, and Practice (Washington, D.C.: Georgetown University Press, 2013), pp. 19–34 Google Scholar.

²⁷ Christiano, “Authority,” p. 5.

²⁸ Ibid.

²⁹ Ibid., p. 6.

³⁰ In fact, the distinction between the two branches of norms has to some extent imploded. See Sloane, Robert D., “The Cost of Conflation: Preserving the Dualism of Jus ad Bellum and Jus in Bello in the Contemporary Law of War,” Yale Journal of International Law 34 (2009), pp. 47–112 Google Scholar.

³¹ I thank Jonathan Parry for suggesting the distinction between the two ways of disaggregating authority.

³² The right to immunize soldiers from personal responsibility is clear when they fight for a government that is held to represent a recognized state, so the question of constitutional authority has some relevance to international law. However, from an international law point of view, this is a matter of representation (who represents the state?), not of identity (which entity?).

³³ The same could be said about the law of neutrality, to the extent that it is still being applied.

³⁴ Just to be clear, if such actors are transformed into nonstate armed groups that correspond to certain prerequisites of chain of command, they may use military violence under this analysis. However, that would require a change of identity of sorts.

³⁵ This has yet to happen, however.

³⁶ Corten, The Law Against War, pp. 279–80.

³⁷ See Neff, War and the Law of Nations, pp. 251–75.

³⁸ Jordan Paust believes that this definition is too relaxed. See his “Armed Opposition Groups,” in Noortmann, Math, Reinisch, August, and Ryngaert, Cedric, eds., Non-State Actors in International Law (Oxford: Bloomsbury Publishing, 2015), pp. 273–92Google Scholar, 281. However, this definition is generally referred to in international law, and for the limited purposes of this paper I have assumed that it is a statement of the law.

³⁹ Many lawyers would, legally speaking, think of this as a limitation of the human right to life rather than as an exception, since human rights apply in principle also during armed conflict.

⁴⁰ The sources of international law are contradictory. For the recognition of a state, the criterion of territorial control is usually the most important issue. The Friendly Relations Declaration, by contrast, conditions the right to territorial integrity on the state being “possessed of a government representing the whole people belonging to the territory without distinction as to race, creed, or colour.” UN General Assembly Resolution 2625 (XXV), A/RES/25/2625, October 24, 1970.

⁴¹ Sir Wood, Michael, “United Nations, Security Council,” Max Planck Encyclopedia of Public International Law (2007)Google Scholar, para. 18. It is controversial whether the powers of the Security Council are self-judging or not. See, for instance, Franck, Thomas M., “The ‘Powers of Appreciation’: Who Is the Ultimate Guardian of UN Legality?” American Journal of International Law 86, no. 3 (1992), pp. 519–23CrossRefGoogle Scholar.

⁴² UN Report of the International Law Commission, 63^rd session (2011), Draft articles on the responsibility of international organizations, with commentaries, UN document A/66/10, p. 113.

⁴³ It is the Swedish government's view that if there is an armed conflict in which an international force is involved, it is that state or organization which leads the force that becomes a party to the conflict. See Engdahl, Ola, “Folkrättsligt ansvar och svenska väpnade styrkors utövande av våld och tvång: vad innebär den svenska Irakinsatsen?” Svensk Juristtidning (2016), pp. 38–61 Google Scholar, 55–56.

⁴⁴ Shraga, Daphna, “UN Peacekeeping Operations: Applicability of International Humanitarian Law and Responsibility for Operations-Related Damage,” American Journal of International Law 94, no. 2 (2000), pp. 406–12CrossRefGoogle Scholar.

⁴⁵ The Korean Armistice Agreement of 1953 was concluded between the Commander in Chief of the United Nations Command, on the one hand, and the Supreme Commander of the Korean People's Army and the Commander of the Chinese People's volunteers, on the other. See news.findlaw.com/cnn/docs/korea/kwarmagr072753.html (retrieved February 10, 2017). It could be argued that UN Security Council Resolution 678 on Iraq in fact contained an agreement between the United Nations and Iraq. See Wrange, Pål, “The American and British Bombings of Iraq and International Law,” Scandinavian Studies in Law 39 (2000), pp. 491–514 Google Scholar, 503.

⁴⁶ The discussion on NLMs builds partly on Wilson, Heather, International Law and the Use of Force by National Liberation Movements (Oxford: Clarendon Press, 1988), pp. 91–136 Google Scholar.

⁴⁷ A salt water (or blue water) colony is a term to distinguish colonies separated by sea from the metropolitan state, such as colonies of the British Empire in Asia and Africa.

⁴⁸ It is likely that they would not be considered NLMs by legal authorities. See Glazier, David W., “Wars of National Liberation,” Max Planck Encyclopedia of Public International Law (2009)Google Scholar. For the purposes of this article it is not necessary to settle the question of whether they fulfill the criteria under international law. Nonetheless, the regulation is relevant from a practical perspective, since the arguments are available and provide a potential political asset.

⁴⁹ Voting figures: 97 (yes); 5 (no); 28 (abstain); 4 (did not participate).

⁵⁰ See Wilson, International Law and the Use of Force by National Liberation Movements, pp. 137–46.

⁵¹ Nolte, Georg, “Intervention by Invitation,” Max Planck Encyclopedia of Public International Law (2010)Google Scholar.

⁵² Charles Beitz would “allow exceptions to the nonintervention principle when intervention would support a secessionist movement that has demonstrated its representative character, when it would contest a prior (and unjustified) intervention by another state, and when it would put an end to acts that ‘shock the moral conscience of mankind.’” Beitz, Charles R., “The Moral Standing of States Revisited,” Ethics & International Affairs 23, no. 4 (2009), pp. 325–47CrossRefGoogle Scholar, 326.

⁵³ In that case the rebels were held to substitute for Qaddafi as legitimate representatives of the Libyan political community, not as an additional legitimate body.

⁵⁴ See, for instance, UN Security Council Resolution 2337, January 19, 2017, operative paragraphs 5 and 6. The Economic Community of West African States was ready to invade Gambia in order to ensure the transfer of power to the newly elected President Barrow. Resolution 2337 does not constitute a legal authorization of that invasion (which later proved unnecessary), but constitutes an implicit political endorsement. Given the absence of clear legal rules, such an assessment would be at least partly political, but it could be informed by legal standards on internal self-determination and human rights as well as by the more traditional standards of effective control.

⁵⁵ Again, Paust believes that this criterion is too relaxed. See Paust, “Armed Opposition Groups,” p. 281. However, it is generally referred to by international lawyers, and for the limited purposes of this paper I have assumed that it is a statement of the law.

⁵⁶ There are some indications that nonstate actors can have human rights obligations, but it is not necessary to settle that issue here.

⁵⁷ Article 2(1)(b) of the 1999 International Convention for the Suppression of the Financing of Terrorism.

⁵⁸ By “law-making,” I mean a resolution that has a general application, and hence does not apply only to specific states, groups, or individuals. Resolution 1373, adopted after 9/11, is a well-known example. In distinction to Resolution 1267 and other similar resolutions, it applies not only to al-Qaeda or any other specified group but to all “entities or persons involved in terrorist acts.” Of course, an armed group could also be subjected to ad hoc sanctions, such as through the aforementioned Resolution 1267. However, for that to happen it is not necessary that the group be determined to engaged in terrorism; under the Security Council's police powers, it can intervene whenever there is a threat to international peace and security. As is well known, how to define a “terrorist group” or entity is a contentious matter, but under relevant international conventions, armed groups are not included under that definition. See, for instance, Article 4(2) of the International Convention for the Suppression of Acts of Nuclear Terrorism, UN document A/RES/59/290: “The activities of armed forces during an armed conflict, as those terms are understood under international humanitarian law, which are governed by that law are not governed by this Convention.” As stated, groups that fall under this carve-out should not be listed as terrorist groups. Armed groups that sometimes use terrorist tactics will, however, be subjected to counterterrorism measures, such as prohibitions of funding, travel restrictions, and the like.

⁵⁹ Clapham, Andrew and Gaeta, Paola, eds., The Oxford Handbook of International Law in Armed Conflict (New York: Oxford University Press, 2014), p. 318CrossRefGoogle Scholar.

⁶⁰ Henckaerts, Jean-Marie, “Study on Customary International Humanitarian Law: A Contribution to the Understanding and Respect for the Rule of Law in Armed Conflict,” International Review of the Red Cross 87, no. 857 (2005), pp. 175–212 CrossRefGoogle Scholar, esp. p. 190 and 198. For a useful discussion, see Lubell, Noam, Extraterritorial Use of Force Against Non-State Actors (New York: Oxford University Press, 2010), pp. 147–55CrossRefGoogle Scholar.

⁶¹ According to rule 159 of the ICRC study of customary law, the authorities actually must “endeavour to grant the broadest possible amnesty to persons who have participated in a non-international armed conflict.” Henckaerts, Jean-Marie and Doswald-Beck, Louise, Customary International Humanitarian Law, Vol. 1 (New York: Cambridge University Press, 2005)CrossRefGoogle Scholar.

⁶² Marco Sassòli, “Transnational Armed Groups and International Humanitarian Law,” Program on Humanitarian Policy and Conflict Research, Harvard University, Occasional Paper Series No. 6 (2006), pp. 1–45.

⁶³ Pictet, Jean S., ed., The Geneva Conventions of 12 August 1949, Commentary, Geneva Convention (III) Relative to the Treatment of Prisoners of War (Geneva: International Committee of the Red Cross, 1960), p. 40Google Scholar.

⁶⁴ See “Practice Relating to Rule 159. Amnesty,” Customary IHL Database, International Committee of the Red Cross, retrieved November 11, 2016, ihl-databases.icrc.org/customary-ihl/eng/docs/v2_rul_rule159.

⁶⁵ Chris Kraul, “Colombian Congress Passes Amended Peace Deal to End Decades of Civil War,” Los Angeles Times, November 30, 2016, www.latimes.com/world/mexico-americas/la-fg-colombia-peace-deal-20161130-story.html.

⁶⁶ For a brief discussion, see Bell, Christine, On the Law of Peace: Peace Agreements and the Lex Pacificatoria (New York: Oxford University Press, 2008), pp. 135–36CrossRefGoogle Scholar.

⁶⁷ See Fabre, “Cosmopolitanism, Just War Theory and Legitimate Authority,” pp. 963–76.

⁶⁸ Chesterman, Simon and Lehnardt, Chia, eds., From Mercenaries to Market: The Rise and Regulation of Private Military Companies (New York: Oxford University Press, 2007)CrossRefGoogle Scholar.

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