1 This relationship between the Contras and the United States is analyzed in depth in International Court of Justice (ICJ), Military and Paramilitary Activities In and Against Nicaragua (Nicaragua v. United States of America), Judgment, 27 June 1986.

2 The link between VRS and the FRY is scrutinized in International Criminal Tribunal for the former Yugoslavia (ICTY), The Prosecutor v. Duško Tadić, Case No. IT-94-1, Judgment (Appeals Chamber), 15 July 1999.

3 For a text on the classification of the situation between Russia and Ukraine, see Laura R. Blank, “Ukraine's Crisis Part 2: LOAC's Threshold for International Armed Conflict”, Harvard National Security Journal (Online), 25 May 2014, available at: http://harvardnsj.org/2014/05/ukraines-crisis-part-2-loacs-threshold-for-international-armed-conflict/ (all internet references were accessed in November 2016).

4 For references on internationalization, see the section on “Control for Internationalization”, below.

5 See, among others, Article 2 common to the four Geneva Conventions of 1949, which states that each of the Geneva Conventions “shall apply to all cases of declared war or of any other armed conflict which may arise between two or more of the High Contracting Parties, even if the state of war is not recognized by one of them”.

6 See common Articles 2 and 3; Article 1, paragraph 3 of Additional Protocol I (AP I); and Article 1 of Additional Protocol II (AP II). Customary IHL also recognizes this IAC-NIAC dichotomy. Indeed, for each rule of the International Committee of the Red Cross (ICRC) Customary Law Study, it is mentioned whether the rule is customary in IACs and/or in NIACs; see the ICRC Customary IHL database, available at: www.icrc.org/customary-ihl/eng/docs/home. For scholars who emphasize this dichotomy, see, among many others, Akande, Dapo, “Classification of Armed Conflicts: Relevant Legal Concepts”, in Wilmshurst, Elizabeth (ed.), International Law and the Classification of Conflicts, Oxford University Press, Oxford, 2012, pp. 37–39 Google Scholar; Milanovic, Marko and Hadzi-Vidanovic, Vidan, “A Taxonomy of Armed Conflict”, in White, Nigel D. and Henderson, Christian (eds), Research Handbook on International Conflict and Security Law: Jus ad Bellum, Jus in Bello and Jus post Bellum, Edward Elgar, Cheltenham, 2013, pp. 272–273 Google Scholar; Kritsiotis, Dino, “The Tremors of Tadić”, Israel Law Review, Vol. 43, No. 2, 2010, pp. 264–266 CrossRefGoogle Scholar.

7 For instance, in the law of NIACs, there is no recognition of the statuses of combatant and prisoner of war equivalent to those existing in the law of IACs. Consequently, in NIACs, members of an organized armed group could, for example, be arrested and prosecuted for their military actions. See, for instance, Kolb, Robert, Ius in bello: Le droit international des conflits armés: Précis, Helbing Lichtenhahn, Basel, 2009, pp. 448–450 Google Scholar; d'Aspremont, Jean and de Hemptinne, Jérôme, Droit international humanitaire: Thèmes choisis, Pedone, Paris, 2012, p. 46 Google Scholar.

8 For more details on these two criteria, see ICTY, The Prosecutor v. Limaj, Bala and Musliu, Case No. IT-03-66, Judgement (Trial Chamber II), 30 November 2005, para. 84; ICTY, The Prosecutor v. Boškoski and Tarčulovski, Case No. IT-04-82, Judgment (Trial Chamber II), 10 July 2008, paras 175–206; ICRC, International Humanitarian Law and the Challenges of Contemporary Armed Conflicts, Report to the 31st International Conference of the Red Cross and Red Crescent, Geneva, 2011, pp. 8–11 Google Scholar; Sivakumaran, Sandesh, The Law of Non-International Armed Conflict, Oxford University Press, Oxford, 2012, pp. 164–180 Google Scholar (and attached references); Cullen, Anthony, The Concept of Non-International Armed Conflict in International Humanitarian Law, Cambridge University Press, Cambridge, 2010, pp. 122–133 CrossRefGoogle Scholar.

9 See United Nations (UN), Draft Articles on Responsibility of States for Internationally Wrongful Acts, with Commentaries, adopted by UNGA Res. 56/83, 12 December 2001 (Draft Articles), available at: http://legal.un.org/ilc/texts/instruments/english/commentaries/9_6_2001.pdf.

10 Article 2 of the Draft Articles states that “[t]here is an internationally wrongful act of a State when conduct consisting of an action or omission: (a) is attributable to the State under international law; and (b) constitutes a breach of an international obligation of the State”. For a detailed analysis of attribution for responsibility of States in international law, see Reymond, Jérôme, L'attribution de comportements d'organes “de facto” et d'agents de l'etat en droit international: Etude sur la responsabilité internationale des etats, Schulthess, Geneva, 2013 Google Scholar.

11 The Draft Articles of the International Law Commission have not yet been adopted by the General Assembly but were annexed to three UN resolutions in 2001, 2004 and 2007. See UN, Meetings Coverage, 6th Committee, GA/L/3395, 19 October 2010.

12 The Draft Articles distinguish between de jure and de facto organs of a State but also between persons or entities exercising elements of governmental authority (Article 5), organs placed at the disposal of a State by another State (Article 6), persons or groups of persons exercising elements of governmental authority in the absence or default of the official authorities (Article 9), and insurrectional or other movements which become the new government of a State (Article 10). These articles are left out of this contribution as they are not fundamental to the issues discussed herein.

13 Note that terminology varies from one author to another and from one instance to another. For example, the ICJ does not consistently use references to de jure or de facto organs.

14 Draft Articles, above note 9, p. 42.

15 Ibid., p. 41.

16 ICJ, Nicaragua, above note 1, para. 109; ICJ, Case Concerning Application of the Convention on the Prevention and Punishment of the Crime of Genocide (Bosnia and Herzegovina v. Serbia and Montenegro), Judgment, 26 February 2007, paras 391–395.

17 According to the ICJ, “to equate persons or entities with State organs when they do not have that status under internal law must be exceptional, for it requires proof of a particularly great degree of State control over them”. Ibid., para. 393.

18 Draft Articles, above note 9, p. 47.

19 Ibid., p. 47.

20 See, for instance, ICTY, Tadić, above note 2, Separate Opinion of Judge Shahabuddeen, para. 4-32; ICTY, The Prosecutor v. Duško Tadić, Case No. IT-94-1, Judgment (Trial Chamber), 7 May 1997, Dissenting Opinion of Judge McDonald, paras 16–34; Milanovic, Marko, “State Responsibility for Genocide”, European Journal of International Law, Vol. 17, No. 3, 2006, pp. 575–604 CrossRefGoogle Scholar; Cassese, Antonio, “The Nicaragua and Tadić Tests Revisited in Light of the ICJ Judgment on Genocide in Bosnia”, European Journal of International Law, Vol. 18, No. 4, 2007 CrossRefGoogle Scholar; Van den Hole, Leo, “Towards a Test of the International Character of an Armed Conflict: Nicaragua and Tadic”, Syracuse Journal of International Law and Commerce, Vol. 32, No. 2, 2005 Google Scholar; Meron, Theodor, “Classification of Armed Conflict in the Former Yugoslavia: Nicaragua’s Fallout”, American Journal of International Law, Vol. 92, No. 2, 1998 CrossRefGoogle Scholar; Byron, Christine, “Armed Conflicts: International or Non-International?”, Journal of Conflict and Security Law, Vol. 6, No. 1, 2001, pp. 66–90 CrossRefGoogle Scholar.

21 ICJ, Nicaragua, above note 1, paras 109–117; ICJ, Genocide, above note 16, paras 398–415.

22 ICTY, Tadić, above note 2, paras 88–145; ICTY, The Prosecutor v. Zlatko Aleksovski, Case No. IT-95-4/I, Judgment, 24 March 2000, paras 130–134.

23 ICTY, Tadić, above note 2, paras 80–87.

24 Ibid., paras 98, 103–104, 117.

25 In the same sense, see ICRC, Commentary on the First Geneva Convention: Convention (I) for the Amelioration of the Condition of the Wounded and Sick in Armed Forces in the Field, 2nd ed., Geneva, 2016 (Commentary on GC I), Art. 2, paras 267–268.

26 ICTY, Tadić, above note 2, para. 116.

27 Ibid., para. 124.

28 Ibid., para. 137.

29 M. Milanovic, above note 20, p. 581. See also L. Van den Hole, above note 20, pp. 280–286, who argues that overall and effective controls do not substantially differ.

30 ICJ, Genocide, above note 16, para. 400.

31 Draft Articles, above note 9, p. 48. See also M. Milanovic, above note 20, pp. 582–583.

32 Draft Articles, above note 9, p. 47.

33 See above note 8.

34 In the same sense, see M. Milanovic, above note 20, pp. 583–588.

35 See the section “Description of the Control Leading to Responsibility”, above.

36 See, among others, ICJ, Genocide, above note 16, para. 404; Marko Milanovic, “What Exactly Internationalizes an Internal Armed Conflict?”, EJIL: Talk!, 7 May 2010, available at: www.ejiltalk.org/what-exactly-internationalizes-an-internal-armed-conflict/; Roscini, Marco, Cyber Operations and the Use of Force in International Law, Oxford University Press, New York, 2014, pp. 138–139 CrossRefGoogle Scholar.

37 ICTY, Tadić, above note 2, paras 103–105.

38 M. Milanovic and V. Hadzi-Vidanovic, above note 6, p. 294.

39 Del Mar, Katherine, “The Requirement of ‘Belonging’ under International Humanitarian Law”, European Journal of International Law, Vol. 21, No. 1, 2010, pp. 108–109 Google Scholar. See also M. Milanovic, above note 20, pp. 583–585.

40 Many authors and instances have underlined the differences between the controls for responsibility and internationalization. See, among many others, ICTY, Tadić, above note 2, Separate Opinion of Judge Shahabuddeen, paras 17–19; ICTY, Tadić (Trial Chamber), above note 20, Dissenting Opinion of Judge McDonald, para. 27; ICJ, Genocide, above note 16, paras 402–406; ICTY, The Prosecutor v. Zejnil Delalić et al., Case No. IT-96-21, Judgment (Trial Chamber), 16 November 1998, paras 230–231; Yuile, Andrew, “At the Fault-Lines of Armed Conflict: The 2006 Israel-Hezbollah Conflict and the Framework of International Humanitarian Law”, Australian International Law Journal, Vol. 16, No. 1, 2009, pp. 197–199 Google Scholar; T. Meron, above note 20, pp. 237–242; C. Byron, above note 20, pp. 83–84.

41 See Articles 28 et seq. of the Draft Articles, above note 9.

42 See, for instance, Articles 53, 57, 82 and 85 of AP I, among other provisions of the Geneva Conventions, Additional Protocols, IHL treaties and customary IHL.

43 See GC IV, Art. 42.

44 See Rosas, Alan, The Legal Status of Prisoners of War: A Study in International Humanitarian Law Applicable in Armed Conflicts, Institute for Human Rights, Åbo Akademi, Turku, 2005, p. 247 Google Scholar; Sassòli, Marco, “Taking Armed Groups Seriously: Ways to Improve their Compliance with International Humanitarian Law”, International Humanitarian Legal Studies, Vol. 1, No. 1, 2010, pp. 15–20 Google Scholar; S. Sivakumaran, above note 8, pp. 72–77.

45 As explained above, States have many obligations when they are parties to an IAC. To ensure the respect of those obligations by an armed group, the State must have close control over the armed group.

46 See, for instance, M. Milanovic and V. Hadzi-Vidanovic, above note 6, pp. 272–273; Johnston, Katie A., “Transformations of Conflict Status in Libya”, Journal of Conflict and Security Law, Vol. 17, No. 1, 2012, p. 85 CrossRefGoogle Scholar; Jed Odermatt, “‘New Wars’ and the International/Non-international Armed Conflict Dichotomy”, International Institute of Higher Studies in Criminal Sciences, 2009, pp. 14–17; Sassòli, Marco, “The Legal Qualification of the Conflicts in the Former Yugoslavia: Double Standards or New Horizons for International Humanitarian Law?”, in Yee, Sienho and Tieya, Wang (eds), International Law in the Post-Cold War World: Essays in Memory of Li Haopei, Routledge, London and New York, 2001, p. 311 Google Scholar.

47 Note that the State's control over an armed group does not necessarily mean that the armed group's members would acquire the status of prisoners of war if caught by another State.

48 See, for instance, Schindler, Dietrich, “The Different Types of Armed Conflicts According to the Geneva Conventions and Protocols”, Collected Courses of The Hague Academy of International Law, Vol. 163, Sijthoff and Noordhoff, Alphen aan den Rijn, 1979, p. 131 Google Scholar.

49 The IAC-NIAC dichotomy is mainly based on the identity of the parties to the hostilities. The law of IACs applies to “armed conflict which may arise between two or more of the High Contracting Parties”, i.e. States (common Article 2), whereas the law of NIACs applies to “armed conflict not of an international character”, i.e. between a State and an armed group or between armed groups (common Article 3). See Rona, Gabor, “Interesting Times for International Humanitarian Law: Challenges from the War on Terror”, Fletcher Forum of World Affairs, Vol. 27, No. 2, 2003, pp. 58–59 Google Scholar; Marco Sassòli, “Transnational Armed Groups and International Humanitarian Law”, Program on Humanitarian Policy and Conflict Research, Harvard University, Cambridge, MA, 2006, p. 4.

50 M. Milanovic, above note 20, p. 581.

51 This is thoroughly explained in the author's PhD thesis. Many authors and instances support partly or totally the different elements of this definition. See the references provided in Carron, Djemila, L'acte déclencheur d'un conflit armé international, Schulthess, Geneva, 2016, pp. 139–200 Google Scholar.

52 See, among many others, ICTY, The Prosecutor v. Duško Tadić, Case No. IT-94-1, Decision on the Defence Motion for Interlocutory Appeal on Jurisdiction (Appeals Chamber), 2 October 1995, para. 70; ICTY, Delalić, above note 40, paras 184, 208; International Criminal Court (ICC), The Prosecutor v. Thomas Lubanga Dyilo, Case No. ICC-01/04-01/06, Decision on the Confirmation of Charges (Pre-Trial Chamber I), 29 January 2007, paras 207–209; ICRC, “How Is the Term ‘Armed Conflict’ Defined in International Humanitarian Law?”, Opinion Paper, Geneva, March 2008, pp. 1–3, 5; UN Human Rights Council, Report of the Commission of Inquiry on Lebanon Pursuant to Human Rights Council Resolution S-2/1, A/HRC/3/2, 23 November 2006, para. 51; D. Akande, above note 6, pp. 40–42; Asada, Masahiko, “The Concept of ‘Armed Conflict’ in International Armed Conflict”, in O'Connell, Mary Ellen (ed.), What Is War? An Investigation in the Wake of 9/11, Martinus Nijhoff, Leiden and Boston, MA, 2012, pp. 55–67 Google Scholar; Kleffner, Jann K., “Scope of Application of International Humanitarian Law”, in Fleck, Dieter (ed.), The Handbook of International Humanitarian Law, Oxford University Press, Oxford, 2013, pp. 44–45 Google Scholar; M. Roscini, above note 36, pp. 132–136.

53 D. Carron, above note 51, pp. 201–254.

54 See above note 8.

55 This “first shot theory” was developed by Jean Pictet in the ICRC Commentaries to common Article 2 in 1952. It is still the view of the ICRC, as confirmed in its Commentary on GC I, above note 25, Art. 2, paras 236–244.

56 See the section “Is it Necessary to Adopt this Control Test for Responsibility in Establishing the Existence of an IAC?”, above.

57 D. Carron, above note 51, pp. 280–301. For example, when interpreting common Article 2 according to the interpretative method of the Vienna Convention on the Law of Treaties, the context must be taken into account (Article 31, paragraph 2 of the Vienna Convention) – notably common Article 3, which establishes the existence of NIACs and of the law of NIACs. The author is of the opinion that the definition of IACs should permit NIACs to exist, as the law of NIACs is the appropriate set of rules to govern hostilities between a State and an armed group. Consequently, it is necessary to have a strong presence of a State behind a potential triggering act of an IAC.

58 ICJ, Nicaragua, above note 1, paras 109–117; ICJ, Genocide, above note 16, paras 398–415. See also the section “Description of the Control Leading to Responsibility”, above.

59 See the section “Is it Necessary to Adopt this Control Test for Responsibility in Establishing the Existence of an IAC?”, above.

60 There are other situations of internationalization like the recognition of belligerency or the acquisition of statehood by the non-State party to a NIAC.

61 See, nevertheless, the section on “Direct Interventions”, below.

62 See, for instance, CNN, “Russian Warplanes Target Georgia”, 9 August 2008, available at: http://edition.cnn.com/2008/WORLD/europe/08/09/georgia.ossetia/.

63 “Direct” and “indirect” interventions are generally the terms used in the doctrine and jurisprudence. See, among others, ICTY, Tadić, above note 2, para. 84; ICC, Lubanga, above note 52, para. 209; J. d'Aspremont and J. de Hemptinne, above note 7, pp. 53–57; R. Kolb, above note 7, pp. 183–186.

64 Many authors analyzed the various situations leading to internationalization (mainly direct and indirect interventions) first, and then scrutinized the level of internationalization in a second phase of analysis. In this second phase, some writings opt for the “theory of pairings”, which classifies hostilities between the two States involved as an IAC and violence between the non-State party and the attacked State as a NIAC. See, for instance, J. d'Aspremont and J. de Hemptinne, above note 7, p. 53. In the author's opinion, it would be better to begin by defining the cases of internationalization (shift from a NIAC to a single IAC) and then to continue by analyzing the criteria for such an internationalization. Therefore, in the case of the “theory of pairings”, in the author's view, there is no transformation of a NIAC into an IAC (no internationalization) but rather the addition of an IAC to a previously existing NIAC.

65 K. Johnston, above note 46, pp. 99–100.

66 See for instance, ICTY, Tadić, above note 2, Separate Opinion of Judge Shahabuddeen, paras 4–32.

67 See above note 63.

68 See, among others, ICC, Lubanga, above note 52, paras 210–211; Commentary on GC I, above note 25, Art. 2, paras 265–273; Schmitt, Michael N. (ed.), Tallinn Manual on the International Law Applicable to Cyber Warfare, Cambridge University Press, Cambridge, 2013, pp. 79–82 CrossRefGoogle Scholar; Vité, Sylvain, “Typology of Armed Conflicts in International Humanitarian Law: Legal Concepts and Actual Situations”, International Review of the Red Cross, Vol. 91, No. 873, 2009, p. 71 CrossRefGoogle Scholar.

69 This question was largely ignored by doctrine and jurisprudence. For a direct intervention to transform a NIAC into a single IAC, some writings require “significant and continuous military action” by the intervening State (ICTY, The Prosecutor v. Ivica Rajić, Case No. IT-95-12, Review of the Indictment Pursuant to Rule 61 of the Rules of Procedure and Evidence (Trial Chamber), 13 September 1996, para. 13) while others are in favour of a less stringent test (ICTY, The Prosecutor v. Dario Kordić and Mario Čerkez, Case No. IT-95-14/2, Judgment (Trial Chamber), 26 February 2001, para. 108; K. Johnston, above note 46, pp. 96–97; S. Sivakumaran, above note 8, p. 225).

70 As explained in above note 64, the majority view is in favour of the “theory of pairings”. See ICJ, Nicaragua, above note 1, para. 219; Ferraro, Tristan, “The ICRC's Legal Position on the Notion of Armed Conflict Involving Foreign Intervention and on Determining the IHL Applicable to this Type of Conflict”, International Review of the Red Cross, Vol. 97, No. 900, 2016, pp. 1240–1251 Google Scholar; D. Akande, above note 6, p. 57; Tamàs Hoffmann, “Can Foreign Military Intervention Internationalize a Non-International Armed Conflict? A Critical Appraisal”, in ISISC, Ninth Specialization Course in International Criminal Law, 2009; M. Milanovic and V. Hadzi-Vidanovic, above note 6, pp. 302–303; Pejic, Jelena, “Status of Armed Conflicts”, in Wilmshurst, Elizabeth and Breau, Susan Carolyn (eds), Perspectives on the ICRC Study on Customary International Humanitarian Law, Cambridge University Press, Cambridge and New York, 2007, pp. 90–91 Google Scholar; D. Schindler, above note 48, pp. 150–151.

71 See section “Description of the Control Leading to Responsibility”, above.

72 See above note 24.

73 See above note 68.

74 See, for instance, ICTY, Tadić, above note 2, paras 88–145. See also ICTY, Aleksovski, above note 22, paras 130–134.

75 M. Milanovic and V. Hadzi-Vidanovic, above note 6, pp. 293–295 (without stating a clear position on the issue); M. Milanovic, above note 36; Momtaz, Djamchid, “Le droit international humanitaire applicable aux conflits armés non internationaux”, Collected Courses of the Hague Academy of International Law, Vol. 292, Martinus Nijhoff, The Hague, 2001, pp. 65–66 Google Scholar.

76 See, nevertheless, ICTY, Tadić, above note 2, Separate Opinion of Judge Shahabuddeen, para. 19.

77 This position is well summed up in S. Sivakumaran, above note 8, p. 227.

78 D. Akande, above note 6, pp. 61–62; R. Kolb, above note 7, pp. 185–186; Stewart, James G., “Towards a Single Definition of Armed Conflict in International Humanitarian Law: A Critique of Internationalized Armed Conflict”, International Review of the Red Cross, Vol. 85, No. 850, 2003, pp. 323–328 Google Scholar.

79 Commentary on GC I, above note 25, Art. 2, paras 265–273. See also T. Ferraro, above note 70, pp. 1234–1240.

80 M. Milanovic, above note 20, p. 581.

81 This is one of the reasons why the ICTY opted for a general control for internationalization. See ICTY, Tadić, above note 2, para. 131.

82 Commentary on GC I, above note 25, Art. 2, para. 271. For the rest, the Commentary on GC I is in favour of an overall control test for internationalization.

83 See the section “Control for Triggering”, above.

84 Both tests require a strict control for intensity. They differ on the scope of the control: specific for triggering, general for internationalization.

85 See the section “Is it Necessary to Adopt this Control Test for Responsibility in Establishing the Existence of an IAC?”, above.

86 Article 1 of the ICTY Statute states that the Tribunal has the power “to prosecute persons responsible for serious violations of international humanitarian law committed in the territory of the former Yugoslavia since 1991 in accordance with the provisions of the present Statute”.

87 See at the section “Is it Necessary to Adopt this Control Test for Responsibility in Establishing the Existence of an IAC?”, above.

88 For a critical approach to international criminal law as an IHL means to enforcement, see Bartels, Rogier, “Discrepancies Between International Humanitarian Law on the Battlefield and in the Courtroom: The Challenges of Applying International Humanitarian Law During International Criminal Trials”, in Matthee, Mariëlle, Toebes, Brigit and Brus, Marcel (eds), Armed Conflict and International Law: In Search of the Human Face: Liber Amicorum in Memory of Avril McDonald, TMC Asser Press, The Hague, 2013 Google Scholar; Sassòli, Marco and Grignon, Julia, ‘Les limites du droit international pénal et de la justice pénale internationale dans la mise en oeuvre du droit international humanitaire’, in Biad, Abdelwahab and Tavernier, Paul (eds), Le droit international humanitaire face aux défis du XXIe siècle, Bruylant, Brussels, 2012 Google Scholar.

89 See, for instance, common Articles 2 and 3.

90 See Article 2, paragraph 7 of the UN Charter.

91 See Articles 28 et seq. of the Draft Articles, above note 9.

92 See common Article 2. See also the section “Control for Triggering”, above.

93 GC III, Arts 25–38.

94 Ibid., Art. 84.

95 See the section “Control for Triggering”, above.

96 S. Sivakumaran, above note 8, p. 224.

97 See the section “Preliminary Remarks”, above.

98 David, Eric, Principes de droit des conflits armés, Bruylant, Brussels, 2012, pp. 171–178 Google Scholar; K. Johnston, above note 46, pp. 97–102.

99 See above note 64.

100 See, nevertheless, D. Akande, above note 6, p. 57; Greenwood, Christopher, “The Applicability of International Humanitarian Law and the Law of Neutrality to the Kosovo Campaign”, in Wall, Andru E. (ed.), Legal and Ethical Lessons of Nato's Kosovo Campaign, International Law Studies, Vol. 78, Naval War College Press, Newport, RI, 2002, pp. 45–46 Google Scholar.

101 See the section “The Test Adopted”, above.

102 See the section “The Test Adopted”, above.

103 As a reminder, for a NIAC to exist, even if the author is in favour of a very low threshold of violence, the degree of hostilities is still one of the two criteria recognized for the emergence of a NIAC. See above note 8.

104 See the sections “Control for Triggering”, above, and “Occupation”, below.

105 See the section “Control for Triggering”, above.

106 Some authors suggest that a NIAC could become an IAC because of the intensity of a second State's direct interventions. See, for instance, Crawford, Emily, “Unequal Before the Law: The Case for the Elimination of the Distinction between International and Non International Armed Conflicts”, Leiden Journal of International Law, Vol. 20, No. 2, 2007, p. 449 CrossRefGoogle Scholar; J. d'Aspremont and J. de Hemptinne, above note 7, p. 58.

107 See above note 49.

108 See common Article 2, paragraphs 1 and 2.

109 For the author's arguments on this point, see D. Carron, above note 51, pp. 372–374, 431–432. For authors following this position, see, among others, ICRC, Expert Meeting: Occupation and Other Forms of Administration of Foreign Territory, ed. Ferraro, Tristan, Geneva, 2012, pp. 124–128 Google Scholar; Arai-Takahashi, Yutaka, The Law of Occupation: Continuity and Change of International Humanitarian Law, and Its Interaction with International Human Rights Law, Martinus Nijhoff, Boston, MA, 2009, pp. 301–304 CrossRefGoogle Scholar; Milanovic, Marko, “Lessons for Human Rights and Humanitarian Law in the War on Terror: Comparing Hamdan and the Israeli Targeted Killings Case”, International Review of the Red Cross, Vol. 89, No. 866, 2007, pp. 384–386 CrossRefGoogle Scholar.

110 The level of sufficient control for indirect occupation is controversial among authors. Interestingly, some writers who are in favour of the overall control for internationalization support a more stringent test for indirect occupation. For further details on indirect occupation, see Commentary on GC I, above note 25, Art. 2, paras 330–332; Ferraro, Tristan, “Determining the Beginning and End of an Occupation under International Humanitarian Law”, International Review of the Red Cross, Vol. 94, No. 885, 2012, pp. 158–160 CrossRefGoogle Scholar, available at: www.icrc.org/en/international-review/article/determining-beginning-and-end-occupation-under-international; J. d'Aspremont and J. de Hemptinne, above note 7, pp. 128–129 (notably note 50); Koutroulis, Vaios, Le début et la fin de l'application du droit de l'occupation, Pedone, Paris, 2010, pp. 31–34 Google Scholar; Sassòli, Marco, “The Concept and the Beginning of Occupation”, in Clapham, Andrew, Gaeta, Paola and Sassòli, Marco (eds), The 1949 Geneva Conventions: A Commentary, Oxford University Press, Oxford, 2015, 1399–1400 Google Scholar. See also ICTY, The Prosecutor v. Prlić et al., Case No. IT-04-74-A, Judgment (Appeals Chamber), 29 November 2017, para. 334.

111 See the section “The Test Adopted”, above.