1. Introduction
The Islamic StateFootnote 1 is a non-state armed group that was part of Al-Qaeda,Footnote 2 which took over territory stretching from Mosul in Iraq to the outskirts of Aleppo in Syria and proclaimed itself a ‘caliphate’ in June 2014.Footnote 3 In response to the threats posed by the Islamic State – with regard to infringement of the sovereignty of Iraq and SyriaFootnote 4 and concern over the harsh human rights abuses in the territories under its controlFootnote 5 – two coalitions were formed to join military forces against the group:Footnote 6 an Islamic Military Alliance, and one with the United States in its forefront (the US-led Coalition).Footnote 7
Since 2014, during several years of intense military operations against the group – in a circle of violence that included the US-led coalition, an Islamic Military Alliance, Russia, Iran, Iraq, Syria, and other non-state actors (NSA) such as the Kurdish Peshmerga – the Islamic State has lost most of the territory in Iraq and Syria that it used to control.Footnote 8 In October 2017 the coalition-backed forces on the ground captured Raqqa, the declared capital of the Islamic State.Footnote 9 By 2019 the Islamic State had lost all the territories it previously held in Iraq and Syria, and the US-led coalition proclaimed the end of the group in these areas.Footnote 10
This article suggests that the campaign against the Islamic State was a battle for the protection of the international legal system and its core values, but it was promoted in a way that threatens the very system it came to defend. In order to illustrate this view, it discusses the military campaign against the Islamic State in Syria during the period in which it attempted to operate as a state, between June 2014 and October 2017. It discusses two legal doctrines: (i) the doctrine of ‘unwilling or unable’, invoked by the United States,Footnote 11 the United Kingdom,Footnote 12 Australia,Footnote 13 CanadaFootnote 14 and TurkeyFootnote 15 during the use of force in Syria; and (ii) the doctrine of responsibility to protect (R2P). Both doctrines promote the use of military intervention when states fail to exercise authority in their territory in a way that erodes state sovereignty – a pillar in the international Westphalian legal system.Footnote 16 As will be shown, both doctrines can also serve as apologetic justifications for the deployment of military force based on political motives.
This article illustrates the gaps in the international legal framework regulating the use of force, and its difficulty in facing challenges such as that presented by the Islamic State: NSAs that control and administer territory and population. The challenge of confronting the group was exacerbated given the need to reconcile state-centred rules with a diverse reality which includes different types of player, some of which are in control of territory and exercise governmental authority despite the fact that they operate in areas belonging to sovereign states. This article proposes the invocation of a functional approach, contrary to a binary approach, which is suitable in complicated cases where several players exercise power in the same territory. Put simply, this article suggests that the Islamic State could have been treated functionally as a state for the purposes of self-defence or collective security measures, instead of invoking doctrines of unclear legal status, such as the ‘unwilling or unable’ doctrine, which might result in undermining the international legal system they are invoked to protect.
The outline of the article is as follows. The next section discusses the international legal framework for the use of force under international law. Later, I will present the rise of the Islamic State and the military campaign that brought about its demise. I will then present the legal justifications raised during the campaign, while focusing on the doctrine of ‘unwilling or unable’, and suggest the functional approach. Finally, I will discuss the response of the Security Council in the fight against the Islamic State.
2. The International Legal Framework Regulating the Use of Force
2.1. Background
The prohibition against the use of force in international law, a jus cogens norm,Footnote 17 is enshrined in Article 2(4) of the Charter of the United Nations.Footnote 18 This rule bars states from using force against other states.Footnote 19 As will be elaborated in this section, this legal field – jus ad bellum – underscores that states are the main players on the international plane as they enjoy the ultimate right under international law: sovereignty.Footnote 20
In accordance with the principle of sovereignty, states may regulate their domestic affairs without foreign interference,Footnote 21 a principal aspect of which is their exclusive right to use force inside their territory.Footnote 22 Indeed, states have traditionally attempted to maintain their exclusivity on the use of force inside their territory. A prominent example, noted by Lustig and Benvenisti, is the Brussels Declaration of 1874 – one of the first comprehensive statements of the modern laws of war – which was a concrete attempt to curtail the activities of NSAs which challenged the exclusive control of states over the use of force, in both wartime and in peacetime.Footnote 23
2.2. The Prohibition on the Use of Force and Its Exceptions
States can protect their rights and interests in areas beyond their own territory, such as on the high seas, which are not part of the territory of any state.Footnote 24 However, when it comes to the sovereign territory of another state, the required legal route for a state to operate militarily is either to invoke one of the recognised exceptions to the prohibition against the use of force or, in the alternative and particularly when operating against an NSA, to receive the consent of the host state the territory from which the group is operating.Footnote 25 As noted by Cheng,Footnote 26 a state can defend its rights against NSAs in the territory of another state by its own action only after it has called upon the sovereign state to afford the necessary protection, and after it has sought the consent of the sovereign before deploying military force.
Today, the prohibition on the use of force between states bars the threat of or the use of military force against another state.Footnote 27 An illegal threat under this rule is an express or implied promise by a state to resort to unlawful use of military force, conditional on non-acceptance of its demands.Footnote 28 There are two exceptions to the prohibition which are stipulated in the UN Charter: (i) authorisation to use force under the collective security system, with authorisation of the Security Council; and (ii) the right of individual self-defence or collective self-defence against an armed attack.Footnote 29 There is also a customary right of self-defence,Footnote 30 and a debate regarding the existence of additional exceptions to the prohibition.Footnote 31 In order for a use of force to qualify as an armed attack justifying a lawful response in self-defence, there is a threshold of gravity in scale and effect.Footnote 32 Once this threshold is met, two further criteria – proportionality and necessity – are required from a state to be met for the exercise of force in self-defence to be lawful.Footnote 33As stated by the International Court of Justice (ICJ), an armed attack must be one which has been elevated to the gravest form of the use of force, compared with other less grave forms of the use of force.Footnote 34 The gap between these two options, sometimes referred to as the Nicaragua gap,Footnote 35 serves as a chilling factor to prevent the escalation of hostilities.Footnote 36 The ICJ stated in the Nicaragua case that an injured state, harmed by violations of international law which do not amount to an armed attack, is generally permitted to take proportionate countermeasures against the injuring state. In the words of the Court:Footnote 37
While an armed attack would give rise to an entitlement to collective self-defence, a use of force of a lesser degree of gravity cannot … The acts of which Nicaragua is accused, even assuming them to have been established and imputable to that State, could only have justified proportionate counter-measures on the part of the State which had been the victim of these acts, namely El Salvador, Honduras or Costa Rica.
As can be seen, while the Court recognised this option, it did not specify what such proportionate countermeasures entail. In a later ruling, the Oil Platforms case, two ICJ judges opined on this issue. On the one hand, Judge Simma suggested that there should be a distinction between full-scale self-defence, triggered by an armed attack in itself, and proportionate countermeasures, which are triggered by an attack falling short of an armed attack.Footnote 38 On the other hand, Judge Higgins finds this issue to be more speculative than established as it is a matter of conjecture.Footnote 39
If we look at Article 22 of the International Law Commission (ILC) Articles on Responsibility of States for Internationally Wrongful Acts (ARSIWA),Footnote 40 lawful countermeasures are acts executed by a state the wrongfulness of which is precluded if they are in response to a prior unlawful act, committed by the state against which the measures are directed, and only if they meet several requirements, such as notification and proportionality.Footnote 41 As is made clear by Article 50(1)(a) of ARSIWA, lawful countermeasures cannot include actions which constitute a threat or use of force as embodied in the UN Charter.Footnote 42 Accordingly, international law does not prescribe for the use of military force which is outside the purview of the Charter, and which can be appraised without reference to it.
A principle of relevance which might preclude wrongfulness of an act is that of necessity – enshrined in Article 25 of ARSIWA.Footnote 43 This principle precludes the wrongfulness of an act which was the only option to safeguard an essential interest in grave and imminent peril if the act did not impair an essential interest of the state towards which the obligations exist.Footnote 44 As I will explain shortly, while this principle theoretically can serve as justification for use of force which contradicts international law, its strict conditions and interpretation generally prevent such an option.
Under Article 25(1)(a) of ARSIWA, necessity may not be invoked if there were other means at a state's disposal to avoid a violation, such as negotiation.Footnote 45 If we look at the case of the Islamic State, we can see that no state tried to negotiate with it, for example, as part of the negotiations over a political transition process in Syria in order to end the conflict.Footnote 46 In fact, even aid organisations feared being prosecuted if they were found to be engaging with the group.Footnote 47 Another condition for this principle is that the actions of a state invoking necessity cannot seriously impair an essential interest of the other state; in other words, the interest relied on by the invoking state must outweigh all other considerations. When it comes to the use of force, certain humanitarian conventions applicable to armed conflict expressly exclude reliance on necessity; generally, in the view of the ILC, the non-availability of the plea of necessity when it comes to the use of force emerges from the object and the purpose of rules of a humanitarian character.Footnote 48 Accordingly, necessity as a legal rule which precludes wrongfulness is less suitable in the context of the Islamic State.
2.3. The Principle of Non-Intervention
Another norm of relevance for the case study of the Islamic State is the principle of non-intervention. This customary rule is anchored in Article 2(7) of the UN Charter, and it stems from the principle of sovereignty.Footnote 49 Notwithstanding its importance and binding legal status, Schachter stated in 1982 that foreign military interventions in civil wars have been so common that it seemed as if the rule of non-intervention had been stood on its head.Footnote 50 Similarly, it has been stated more recently by Schmitt and Wall that this principle is more apparent in its breach than in its observance.Footnote 51 Still, as will be shown in this article, this customary rule is of relevance to the case of the Islamic State.
The ICJ has instructed that in order for an intervention to be considered illegal, two elements must be examined. First, illegal intervention deals with matters regarding which a sovereign state is free to decide on its own, such as its political or economic system.Footnote 52 Second, illegal intervention must involve coercion.Footnote 53 In simple words, intervention occurs when there exists a coercive interference by a state in the internal or foreign affairs of another state.Footnote 54 In practice, organising, instigating, assisting, financing or participating in insurrections in favour of an NSA engaged in hostilities against the sovereign government, or against other NSAs, constitutes unlawful intervention.Footnote 55 As stated by the ICJ in the Nicaragua case, other forms of involvement in civil wars can also amount to a violation of the principle of non-intervention, such as humanitarian assistance on a selective basis intended to assist only one specific NSA and not the entire larger population, as was given by the United States in that case.Footnote 56 In comparison, the US cessation of economic aid, and the imposition of import restrictions and trade embargo against Nicaragua, were not considered to have violated this principle.Footnote 57 In recent years, cyber capabilities allow for new ways of non-physical intervention, which brought back the focus on the principle of non-intervention, in order to perform manipulation of elections or other attempts to influence public opinion.Footnote 58 As will be shown, this principle is of relevance when it comes to the use of force in Syria as part of the military campaign against the Islamic State.
2.4. The State-Centred Nature of Jus ad Bellum
Jus ad bellum as a legal concept reflects a state-centred perception in that it lies firmly on the understanding that states are the main players.Footnote 59 Henkin suggested that the state system traditionally is committed to territorial integrity, a particular manifestation of state sovereignty, which excludes all forms of external intervention, even for noble purposes.Footnote 60 In the traditional view of the ICJ, reflecting a state-centred perspective, the scope of the principle of territorial integrity is confined to the sphere of relations between states,Footnote 61 which excludes NSAs. Another aspect of this discussion is the debate over the existence of a right of self-defence against an NSA.Footnote 62 There are two main approaches in this regard. On the one hand, the Security Council has recognised the right of self-defence in the context of terror attacks conducted by NSAs.Footnote 63 By contrast, the ICJ has presented a significantly more traditional and state-centred perspective. In the view of the Court, if a state wishes to treat an attack by an NSA as an armed attack and to respond based on the right of self-defence, there is first a need to attribute the act to a sovereign state.Footnote 64 Against this backdrop, some claim that there is no right to use force against an NSA on the territory of another state unless some form of attribution to a state exists,Footnote 65 while others believe that states that fall victim to an attack by an NSA that meets a certain level of gravity may respond with the use of military force.Footnote 66 In any case, even if states are entitled to use force against NSAs in the territory of a third state, they must first seek the consent of the host state before they can use military force in that territory.Footnote 67
As for the question of whether the prohibition on the use of force applies to NSAs as it applies to states,Footnote 68 the uncertainty is even greater. The traditional interpretation of Article 2(4) of the UN Charter is that the prohibition anchored in it applies only to use of force among states.Footnote 69 Corten, for example, believes that at present there is no general agreement which expands the prohibition on the use of force to relations which are not among states.Footnote 70 When discussions on the definition of aggression took place at the UN General Assembly, several states (Australia, Canada, Italy, Japan, the United States and the United Kingdom) suggested that the prohibition against the use of force applies to all political entities which are delimited by internationally recognised lines of demarcation or boundaries.Footnote 71 Eventually, the definition suggested by the General Assembly in 1974,Footnote 72 which was the predominant definition of aggression and the basis for the modern rule in the Statute of the International Criminal Court (ICC),Footnote 73 focused on the use of force by states, reflecting the state-centred preference of international law generally and particularly jus ad bellum. Footnote 74 One exception to the focus on states was Article 3(g) of the resolution which prohibited the use by a state of armed bands, or other types of NSA,Footnote 75 in order to carry out acts of armed force against other states; this is still a reference to NSAs but from a Westphalian perspective. An additional exception was Article 7 of the resolution, which states that nothing in the definition of aggression could in any way prejudice the right of self-determination, freedom and the independence of peoples forcibly deprived of that right, particularly people under colonial, racist or other forms of alien domination, and it also cannot deprive such people of the right to struggle in accordance with the principles of the UN Charter and in conformity with it.Footnote 76
The view presented in the General Assembly resolution defining aggression, along with additional General Assembly resolutions which dealt with self-determination and the struggle against oppression, brought Samuel,Footnote 77 Wolfrum and Philipp,Footnote 78 to claim that NSAs can resort to forceful measures in their exercise of self-determination against alien subjugation,Footnote 79 colonialism,Footnote 80 racist regimesFootnote 81 or foreign occupation,Footnote 82 without violating the prohibition on the use of force. Regardless of whether this is indeed the case, it must be stressed that none of these exceptional situations are relevant to the case of the Islamic State, as will be elaborated in the next section. Another line of reasoning, noted by Tsagourias,Footnote 83 is that once the prohibition on the use of force reached customary statusFootnote 84 it became binding on all international actors, including NSAs. Tsagourias believes that his view is reflected, for example, in the view of the ICJ in its Reparations Advisory Opinion, which dealt with the status of the United Nations as an international player. Here, the Court stated that subjects of law in any legal system are not necessarily identical in their nature or in the extent of their rights.Footnote 85 Put simply, the UN has international personality but it does not make it a state as not all legal players are the same.
In conclusion, the question of whether the prohibition on the use of force applies exclusively to relations among states remains controversial. This disagreement reflects more generally tensions which are created in attempting to reconcile state-centred rules with a reality that is much more diverse and includes other players such as NSAs. The following sections highlight even more the difficulty of applying jus ad bellum in the context of the Islamic State, which presented a unique and significant challenge before the international community.
3. The Case Study: The Islamic State in Iraq and Syria
The Islamic State took over significant territories in Iraq and Syria, and attempted to establish its authority and govern these territories between 2014 and 2017.Footnote 86 In order to do so, the group provided basic services, such as infrastructure maintenance and development,Footnote 87 through a sophisticated bureaucratic structure.Footnote 88 It also employed a harsh penal and administrative system comprised of the Al-Hisbah morality police, the general police force, courts and entities which managed recruitment, tribal relations and education.Footnote 89
At its height, the Islamic State was considered to be the richest terrorist group in history, as it gained wealth by virtue of oil smuggling, theft, the sale of antiquities, and significant taxation of many aspects of life in the wide territories under its control.Footnote 90 While it used to be concentrated in certain areas in Syria and Iraq,Footnote 91 as the reputation and capabilities of the Islamic State developed, the geographical scope of the threat it posed became vast given the group's appeal to foreigners who chose to join the group and act on its behalf in different parts of the world.Footnote 92
The Islamic State's vision of statehood draws inspiration from Wahhabism, a doctrine originating in the thirteenth century, which promotes political organisation as a religious monotheistic state.Footnote 93 Hence, it is perceived as a religious alternative to the secular legal and social system underlying the international order.Footnote 94 In other words, the Islamic State rests on a theological-political basis, in contrast to the Westphalian legal order, which rests fundamentally on human consent, without the necessity of attachment to religion.Footnote 95
A turning point in the international attention directed at the group occurred when the Islamic State was accused of committing acts of murder, abduction, expulsion, rape and other human rights violations against the Yazidi minority in Iraq.Footnote 96 In response, two coalitions were formed to join military forces fighting against the group.Footnote 97 The US-led coalition operated in the territories under the group's control both in IraqFootnote 98 and in Syria.Footnote 99 In addition, the US-led coalition provided training and equipment for groups involved in hostilities against the Islamic State from the ground,Footnote 100 such as the Kurdish Peshmerga.Footnote 101 Other measures have also been taken, such as the imposition of sanctions against individuals, groups and entities which provided support to the Islamic State (in terms of financing, arming, planning and recruiting).Footnote 102 In the midst of all of these occurrences Syria asked Russia to provide military assistance in combating the Islamic State and other terrorist groups operating in Syria.Footnote 103 As can easily be seen, the international involvement in the Syrian context was neither unified, nor did it speak in a single voice. Instead, different states adopted diverse allies in the conflict and supported them in various ways. In particular, Turkey, Saudi-Arabia, Jordan, Qatar, the US, the UK and France supported Syrian opposition,Footnote 104 while Russia and Iran provided military support, training, equipment and arms to the Syrian government forces, alongside reinforcement from Hezbollah, which deployed its members in Syrian territory to support the Assad government.Footnote 105
The use of force in Iraq was justified by Iraq's request for assistance;Footnote 106 hence this consent precludes any wrongfulness on the part of the intervening states from the perspective of jus ad bellum.Footnote 107 Syria, by contrast, voiced its disapproval of the use of force in its territory against the Islamic State and of assistance provided to opposition NSAs operating in its territory,Footnote 108 with the exception of Russia and Iran which had been invited to assist the Syrian government.Footnote 109 Pursuant to this, the discussion below of the legality of the military campaign against the Islamic State will focus on the use of force in Syria, as the campaign in Iraq does not raise significant legal questions relating to jus ad bellum.
The international intervention against the Islamic State incentivised the latter to operate outside Iraq and Syria. An illustrative example is the chain of attacks that took place on 13 November 2015, when operatives of the group simultaneously attacked six locations in Paris (France), taking the lives of 126 persons in the most significant attack on French soil since the Second World War.Footnote 110 This deadly attack drew momentous attention, yet it was far from being the only major attack outside Iraq and Syria. During the period 2015 to 2019, more than 2,000 people lost their lives in Islamic State-related attacks outside Iraq and Syria, with two notable attacks being the shooting in Sousse (Tunisia) when 38 people died, and the bombing of a Russian aircraft in Sinai (Egypt), killing 22 people.Footnote 111
In Syria and Iraq, where the Islamic State attempted to establish its caliphate, the US-led coalition started to conduct air strikes against areas held by the group. In Iraq this began in August 2014,Footnote 112 and September 2014 in Syria.Footnote 113 Some attacks also took place outside Iraq and Syria, such as in Libya.Footnote 114 The air strikes against the Islamic State included significant military strongholds as well as strategic targets like oil fields, and against leaders of the group.Footnote 115
During the period 2014 to 2017, the US-led coalition conducted over 10,000 bombing missions in Iraq and Syria against the Islamic State, leading to tens of thousands of casualties and significant destruction of private and public property.Footnote 116 Since the beginning of this campaign Syria and Russia have opposed it and called it an act of aggression.Footnote 117 During three years of intense military operations against the group, the Islamic State lost most of the territory in Iraq and Syria that it used to control,Footnote 118 and its income has declined significantly.Footnote 119 In October 2017 the coalition-backed forces on the ground captured Raqqa, the declared capital of the Islamic State.Footnote 120 In the view of some states – including Iraq, Russia and Iran – this move marked the end of the Islamic State, or at least the end of the project of the caliphate.Footnote 121
By 2018 the Islamic State held only a small percentage of the territory it took over in 2014, and only around 1,000 members of the group remained in Iraq and Syria.Footnote 122 As time moved on, and the territory under the control of the group dwindled, the Islamic State shifted its focus from attempting to govern the territory to its old tactics. The once self-proclaimed caliphate has transformed back into a more traditional terrorist group with clandestine networks of cells engaged in guerrilla attacks, bombings and targeted assassinations.Footnote 123 By March 2019 the Islamic State had lost all the territories it previously held in Iraq and Syria.Footnote 124 On 27 October 2019, the leader of the group, Abu Bakr al-Baghdadi, was killed during a raid led by the US.Footnote 125
As can be seen, the Islamic State suffered a significant demise in Iraq and Syria, which seems final. Yet, it is too soon to declare the end of the Islamic State because the group still poses a threat in two main respects. First, it still has affiliates in various states around the world, such as Algeria, Afghanistan, Egypt, Libya, Malaysia, Nigeria, the Philippines and Somalia.Footnote 126 Hence, it is still possible that the Islamic State will pursue the establishment of a caliphate in a different part of the world under its control,Footnote 127 as the group has already demonstrated its ability to make use of the benefit of political resentment of disenfranchised Sunni Muslims in Shia-dominated Iraq in order to regroup and resurrect in a new and improved form.Footnote 128 Second, many fighters with the Islamic State have made their way to other states, including in the West and, in particular, in Europe.Footnote 129 Accordingly, sleeper cells may have been put in place in the United States, Europe and other Western states long before the battlefield losses mounted.Footnote 130 Returning fighters may decide to engage in terror attacks or promote radicalisation, sectarian tensions, and maybe even some form of a political renaissance for the idea that the Islamic State symbolises.Footnote 131
4. The Legality of the Military Campaign against the Islamic State in Syria
Syria protested against two main aspects of the military efforts against the Islamic State: (i) the use of military force in its territory without its consent; and (ii) granting assistance to opposition NSAs operating in Syria.Footnote 132 The exceptions, as noted, were from Russia and Iran, which were invited to assist the Syrian government.Footnote 133 This section will present justifications raised by leading states in the US-led coalition, and then discuss the nature and legality of the doctrine of ‘unwilling or unable’. It will then examine whether Syria was indeed unwilling or unable to combat the Islamic State, and finally it will suggest a functional approach as the way forward.
4.1. Legal Justifications for the Use of Force in Syria
One justification put forward for the use of force in Syria without the latter's consent, invoked by Germany and Belgium, was that the request of the government of Iraq to assist it in the fight against the Islamic State, as part of an effort of collective self-defence, includes the ability to use force in areas in Syria.Footnote 134 This justification portrays the military effort as the realisation of the right of collective self-defence against the Islamic State on behalf of Iraq.Footnote 135 The problem, however, is that Iraq can only consent to the deployment of military force in its territory; it has no authority relating to the territory of neighbouring Syria. Such a broad reading of the right of collective self-defence carries the potential to affect the scope and duration of the right to use military force under Article 51 of the UN Charter. In addition, this justification conflicts with the view of the ICJ, according to which self-defence applies against NSAs provided their actions can be imputed to another state.Footnote 136
As for the United Kingdom, it contended initially that it is using force in the exercise of inherent individual and collective self-defence, based on Iraq's invitation. This justification is another broad reading of the right of collective self-defence, as was raised by Belgium and Germany. In a note sent to the Security Council, it was stated that the UK attacked a specific target in Syria that had planned and directed an imminent armed attack against it.Footnote 137 The note does not specify who the target was, the armed attacks that were planned, or any other relevant piece of information which could help to appraise the validity of its proposition. The factual ambiguity can be explained by reasons of national security, but the lack of a proper legal basis cannot be justified in a similar manner.Footnote 138 While the UK can reply to an armed attack against it, there is doubt whether it can act in an anticipatory fashion to prevent it beforehand in the face of an attack (especially when the gravity of the attack is unclear); even if there was an initial right to use force, the existence of a threat, as well as its imminence, should be appraised. On the other hand, there are, naturally, more expansive views. For example, Reisman and Armstrong claim that imminence is interpreted more flexibly in state responses to terrorist organisations;Footnote 139 Hakimi believes that anticipatory self-defence might already be shifting, or might soon shift, towards the more permissive view.Footnote 140 In any case, the decision of the UK to employ vague legal explanations is worrying as it is a permanent member of the Security Council, and hence it is doubtful that the Council would be able to limit its operations.
Vague explanations by the United Kingdom, along with unconvincing explanations presented by Belgium and Germany at the earlier stages of the military campaign, indicate that states involved in the military campaign against the Islamic State allowed themselves greater ‘leeway of justification’ as the Security Council was unable to authorise the use of military force against the Islamic State,Footnote 141 and given the international support – almost consensual – for the need to fight the group.Footnote 142 In simple words, it might have been easier to present controversial justifications against the Islamic State, in the context of the prolonged and disastrous civil war in Syria, and to portray it as a ‘lesser evil’. Nevertheless, we must recall that while the military campaign against the group was successful in terms of driving it away from the territories it occupied, it is not at all clear that the general welfare of the Syrian population improved as a result; nor did the military campaign prevent attacks against civilians by players other than the Islamic State – most notably the Syrian government.Footnote 143
A more nuanced argument has been put forward by the United States, another permanent member of the Security Council and leader of the most prominent coalition against the Islamic State. The US originally raised several claims to support its use of force in Syria,Footnote 144 but its main and most consistent claim is that Syria is ‘unwilling or unable’ to address the threat of the Islamic State; thus, the coalition is entitled to act against it in the course of action in self-defence.Footnote 145 The doctrine of ‘unwilling or unable’ has been raised in the past only by the USFootnote 146 in order to justify drone strikes in, for example, Yemen, Afghanistan, Pakistan and Somalia.Footnote 147 In the context of the Islamic State, after the US paved the way for this claim it has also been raised by Australia,Footnote 148 Canada,Footnote 149 the UKFootnote 150 and Turkey.Footnote 151 The military campaign against the Islamic State is a critical juncture in the development of the doctrine, and I will now turn to discuss its nature and legality, and if indeed its main condition was met (whether Syria was ‘unable or unwilling’ to fight against the Islamic State).
4.2. The Doctrine of ‘Unwilling or Unable’ in International Law
There is much discussion over the question of whether using military force violates Article 2(4) of the UN Charter when a state is ‘unwilling or unable’ to act.Footnote 152 In particular, there is disagreement relating to the status of the doctrine as an alleged exception to the prohibition against the use of force and, more generally, about its legal status under international law.Footnote 153 Before delving into the legal status of the doctrines, some preliminary remarks on its nature are due.
As observed by Maogoto, doctrines that override considerations of consent, like ‘unwilling or unable’, and push the limits of the existing law, reflect a new reality that erode positivist tendencies of the international legal system.Footnote 154 Lorca, while tracing the origins of the ‘unwilling or unable’ doctrine, argues that it derives from the resort of powerful states, at the height of Western colonialism during the nineteenth and early twentieth centuries, to justify interventions – by force or diplomatic means – in pursuit of international claims, concerning the life or property of nationals residing abroad.Footnote 155 In his view, since the nineteenth century, voices from non-Western states have contested the legality of interventions to recover damages, and these efforts culminated in the recognition of the principle of non-intervention in the 1933 Montevideo ConventionFootnote 156 and then in the UN Charter.Footnote 157 Pursuant to this, Gathii notedFootnote 158 that the modern invocation of ancient doctrines, such as the invocation of ‘unwilling or unable’, reveals imprints of colonialism and imperialism.Footnote 159
The ‘unwilling or unable’ doctrine also recalls a return to medieval structures, namely the invocation of legal norms which are characterised by their relative autonomy from existing law,Footnote 160 and by the fact that they spring from social lifeFootnote 161 – that is, bottom up.Footnote 162 One example is the medieval institution of chivalry, which comprised customary regulations of gallant demeanour for the actions of knights;Footnote 163 another is the medieval lex mercatoria, created by the merchant community.Footnote 164 Historically, before the emergence of jus ad bellum, just-war theories prevailed with some version of a ‘legitimate authority’ constraint, construed as a necessary condition for war.Footnote 165 The principle of ‘legitimate authority’ maintained that a rightful entity can impartially declare war or evaluate whether war is just.Footnote 166
The doctrine of ‘unwilling or unable’ evokes medieval structures in two respects: (i) it is a bottom-up course of action that states take relative autonomy from existing law – as the doctrine of ‘unwilling or unable is currently not part of the lex lata, and; (ii) states take back their role as the legitimate authority which decides that the use of military force is just, even if not as part of self-defence, and diminishes the role of the Security Council as the modern ‘legitimate authority’ entrusted with maintaining international peace and security since the establishment of the UN. If the doctrine of ‘unwilling or unable’ evolves into a binding norm, this might lead to a radical change in the United Nations collective security system with the Security Council at the heart of it.Footnote 167
Against this backdrop, I shall move to focus on the legal status, if such indeed exists, of the doctrine. According to Scharf,Footnote 168 use of force in the territory of a ‘failed state’ would not violate territorial integrity if that state does not exercise meaningful control over its borders and territory.Footnote 169 Returning to the legal status of the doctrine of ‘unwilling or unable’, in Scharf's viewFootnote 170 several developments generated a Grotian Moment,Footnote 171 leading to a new rule of customary international law concerning use of force against NSAs. The developments to which Scharf refers are the international military and legal responses to three main events: (i) the systematic Al-Qaeda terrorist attacks against the World Trade Centre and US Pentagon on 11 September 2001;Footnote 172 (ii) the attacks by the Islamic State on the Russian airliner in Sinai on 31 October 2015; and (3) the chain of Islamic State attacks that took place in Paris on 13 November 2015.Footnote 173
Corten, by contrast, believes that the main justification of the US when it comes to the use of force in Syria, the doctrine of ‘unwilling or unable’, is not legally valid. This is because it was not accepted as positive law by states, not even by most of the members of the US-led coalition, as even the states that invoke this doctrine did not demonstrate a genuine legal conviction that the doctrine reflects existing international law (lex lata), or a developing or desired norm (legi ferenda). Rather, they referred to their moral obligation to act in the Syrian context.Footnote 174 The two most prominent examples are (i) the statement by the Canadian Minister of Foreign Affairs made during a debate in the Canadian House of Commons that there was no legal basis for any intervention in Syria because of the absence of authorisation by the Syrian government; and (ii) the Australian Prime Minister expressed his doubts regarding the legality of the strikes in Syria without the consent of the Syrian government.Footnote 175 Tsagourias and Kajtar have also criticised the claim that this doctrine acquired a status under international law, and noted that it does not resolve legally the issues arising from the fact that the actions were taken against an NSA in the territory of another state.Footnote 176
The legal status of the doctrine of ‘unwilling or unable’ is vague as it is not anchored in any legally binding document and was never recognised as a customary or a general principle by any judicial body.Footnote 177 The campaign against the Islamic State is the first occasion on which states other than the US have resorted to invoking the doctrine; yet notably only a portion of the US-led coalition resorted to this claim.Footnote 178 As noted, even those who did (such as Australia and Canada) had their own doubts about the legality of the doctrine and its invocation.Footnote 179 Additional scholars to those already mentioned – such as Peters,Footnote 180 Acharya,Footnote 181 and LustickFootnote 182 – doubted the legal status of the doctrine and noted the problems it raises. In fact, as will be explained in the next subsection, even if this doctrine has acquired a status under international law, it is not obvious that it was met in the case of the Islamic State (as Syria was willing and able to fight against the group). Nevertheless, we can see that the doctrine grew stronger in practice during the military campaign against the Islamic State. Why did this occur?
In my view, a main reason is that the campaign was not just an armed conflict against an NSA; rather, it was a battle for the protection of the international legal system and its core values. As noted, the Islamic State vision of statehood originates from the thirteenth century,Footnote 183 and it rests on a theological-political basis, contrary to the Westphalian legal order, which rests fundamentally on human consent without attachment to religion.Footnote 184 Delahunty suggested that the Islamic State rejected two axioms of the international order: first, it claimed that the basis of the international legal order must be founded on the sacred, not the secular; second, it claimed the authority to represent the entire global community of Muslims while disregarding other existing sovereign Muslim states.Footnote 185 Interestingly, in Corten's view the possible crystallisation as a binding norm of ‘unwilling or unable’ would lead to a radical change in, if not the end of, the United Nations collective security system.Footnote 186 In that sense, leading US-led coalition member states went on a battle to protect the system, but they did so in a way that jeopardises the UN collective security system – a main pillar in the maintenance of peace and order in this international legal system.
In conclusion, the status of the doctrine of ‘unwilling or unable’ under international law is not clear, and its content is vague.Footnote 187 Still, we cannot ignore the fact that the United States,Footnote 188 the United Kingdom,Footnote 189 Australia,Footnote 190 CanadaFootnote 191 and TurkeyFootnote 192 invoked it in order to deploy military force in Syria. Accordingly, I will focus now on the main question that one must answer when invoking this doctrine. Was Syria indeed unwilling or unable to fight the Islamic State in its territory?
4.3. Was Syria Unwilling or Unable to Fight the Islamic State?
As a preliminary matter, one should recall that the military campaign in the territory of Syria included numerous players with different allegiances and legal reasoning for their participation in the campaign. The Syrian opposition was composed of different NSAs, some working together and some against the other groups,Footnote 193 and they were supported by Turkey, Saudi-Arabia, Jordan, Qatar, the United States, the United Kingdom and France. On the other hand, Russia and Iran supported the Syrian government forces, and they received reinforcement from Hezbollah, which deployed its members in Syria.Footnote 194 As I will show, the states that invoked the doctrine of ‘unwilling or unable’ did not engage in a dialogue with Syria, and even ignored Syria's pleadings and objections regarding the use of force on Syrian territory without its consent.
In earlier stages of the conflict there was an attempt to establish a Syrian National Coalition, claiming to be the legitimate representative of the Syrian people as a government-in-exile of Syria, but it was unable to deliver significant diplomatic or material support for the opposition, and it lost its impact and legitimacy both inside and outside Syria.Footnote 195 While such attempts to delegitimise the Syrian government were made, Syria consistently reaffirmed, before the Security Council,Footnote 196 its sovereignty over its territories, and particularly the areas controlled by the Islamic State. The Security Council also continuously recognised the territorial integrity of Syria.Footnote 197
The fact that Syria is engaged in hostilities and invites other sovereign states to assist itFootnote 198 raises doubt as to the question of whether it is unwilling to fight the Islamic State, as claimed by the US,Footnote 199 the UK,Footnote 200 Australia,Footnote 201 CanadaFootnote 202 and Turkey.Footnote 203 Syria has stressed continuously in its dialogues with the Security Council that its competent institutions and agencies continue to fulfil their responsibilities in accordance with international law, and that it is both determined to eliminate what it terms as terrorism on its territory and is, at the same time, open to cooperate with other states in the struggle; hence, states should not operate without its consent on its territory.Footnote 204 Syria also explained that NSAs that operate against it undermine its sovereignty; hence, the financial and military assistance granted by states to NSAs operating in Syria constitutes, according to the Syrian government, a violation of the principle of non-intervention.Footnote 205 Deeks, in attempting to formulate the normative framework for the ‘unwilling or unable’ doctrine, has emphasised the need for any state that wishes to invoke this doctrine first to attempt to obtain the consent of the territorial state.Footnote 206 In the present case the US-led coalition member states that invoked the doctrine did not attempt to obtain Syria's consent for the use of force on its territory, and they ignored Syria's objections to any use of force on its territory without its consent and coordination.
In my view, the disregard of Syria's desire to choose its partners during the military campaign against the Islamic State endangers the stability of the prohibition against the use of force. The invocation of the doctrine of ‘unwilling or unable’ also illustrates two concepts introduced by Koskenniemi:Footnote 207 (i) concreteness (apology), and (ii) normativity (utopia). An argument about concreteness is an argument about the closeness of a particular principle to state practice, while an argument about normativity seeks to demonstrate the rule's distance from state will and practice and from politics.Footnote 208 In Koskenniemi's view, neither claim is sustainable alone, as the argument about concreteness is an apology for the exercise of force (when it is used to establish effective control over a territory), while an argument about normativity is abstract and begs the question of whose application of the external criterion should receive precedence.
In sum, the invocation of the doctrine of ‘unable or unwilling’ was an apologetic justification for the use of force which contravenes state sovereignty. Currently there are two perceptions of Syria's capacity and willingness to cooperate with other states: one advocated by Syria itself,Footnote 209 and the other by US-led coalition member states;Footnote 210 it is not clear which view deserves prominence.Footnote 211 This reveals that at times legal concepts of a binary nature are less useful in a complicated and nuanced reality within which several elements of different legal concepts can exist in a mixed fashion.Footnote 212 The military campaign against the Islamic State was indeed complicated, and nuanced, as elaborated above. Pursuant to this, the next subsection will suggest a possible solution: consideration of a functional approach in the field of jus ad bellum, by analogy with the increasing use of a functional approach in other contexts.Footnote 213
4.4. From Apology to Functionalism: A Possible Way Forward
In many fields the law offers clear-cut dichotomies. A classic example is an age limit that decides who is entitled to vote or is eligible to face criminal prosecution.Footnote 214 Another example from the field of international humanitarian law (jus in bello) is the division between combatants and civilians, which has significance for a multitude of questions – relating to targeting, detention, property rights and more.Footnote 215 In the field of jus ad bellum, the focus of this article, one can note the questions discussed above. Does an attack constitute an armed attack in the sense of Article 51 or not?Footnote 216 Is the scope of the principles of territorial integrityFootnote 217 and self-defenceFootnote 218 confined only to the sphere of relations between states and therefore excludes NSAs?
The invocation of clear-cut triggering norms can impact on the application of an entire legal regime, as the existence of an armed attack would trigger the application of jus ad bellum. Generally, clear-cut triggering norms aim to generate a high measure of legal certainty and lower implementation costs.Footnote 219 In the present case there is a need to reconcile the fact that the Islamic State for three years controlled different areas and exercised certain governmental authorities with the fact that, regardless of what occurred on the ground, the areas still remained under the sovereignty of Iraq and Syria. This complexity derives from the tension between the legal perception of the situation and the actual conditions on the ground. A possible solution could be the invocation of a functional approach in the field of jus ad bellum, by analogy with the increasing use of a functional approach in other fields, such as statehoodFootnote 220 and the law of occupation.Footnote 221 I will shortly present the invocation of a functional approach in these two fields, and then return to discuss how it can also assist when it comes to jus ad bellum, and particularly when it comes to a challenge such as that presented by the Islamic State.
In the context of occupation, there is a growing tendency to analyse functionally the existence of a situation of occupation. For example, the Ethiopia-Eritrea Claims Commission found that when an army is present in an area of a hostile state on a transitory basis, not all the obligations of an occupant can reasonably be applied, but some of them may.Footnote 222 In simple words, the legal obligations of an occupant arise in correlation with its actual exercise of governance power.Footnote 223 As noted by Gross, the Commission suggested a position that differentiates between obligations on the basis of the capacity and power exercised by the occupying power rather than on a formalist on/off definition of occupation.Footnote 224 The rationale underlying this view is the need to consider how to allocate responsibility in a situation where control and governance power are shared and exercised by several entities – including an NSA (just like the Islamic State).Footnote 225 This approach is evident in other judicial decisions, such as the Naletilic case before the International Criminal Tribunal for the former Yugoslavia (ICTY),Footnote 226 and it was also adopted by the International Committee of the Red Cross (ICRC) in its updated commentaries on the Geneva Conventions.Footnote 227
With regard to statehood, in recent decades there has been an increase in the invocation of functionalism in the application of the statehood criteria towards quasi-states,Footnote 228 in the sense that quasi-states have been treated as states for certain purposes, as they were considered to possess state-like features in certain respects. The invocation of functionalism in this field of law places the emphasis on governance, namely the provision of services by the state or by different players with a better capacity to do it, together with the execution of its policy,Footnote 229 rather than on the traditional Montevideo Criteria,Footnote 230 which illustrate the Westphalian notion of the sovereign state.Footnote 231 Shany noted that quasi-states tend to be regarded functionally as states if and when the differences between them and states are viewed as irrelevant for the purposes of the institution or treaty at hand, and that the decision should be made in light of the nature and function of the legal arrangement in question.Footnote 232 Examples for this approach include India's membership of the United Nations before its independence,Footnote 233 and the participation of Taiwan and Puerto Rico in the work of several intergovernmental organisations.Footnote 234
The advantage of a functional approach is that it allows for a more nuanced analysis of a situation, compared with a binary approach,Footnote 235 in complicated cases where several players exercise power in the same territory. In the present case, military power was applied by the various players in Iraq and Syria and, at the same time, sovereign-like power was applied by the Islamic State, which had established de facto authority over part of the territory. In this complicated reality, the Islamic State could have been treated functionally as a state for the purposes of self-defence or collective security measures, instead of invoking legal doctrines of unclear legal status such as ‘unwilling and unable’. This suggestion correlates by analogy with the solution of jus in bello to situations in which violence between a state and NSAs crosses a certain threshold of intensity, and especially when the group exercises effective control over territory. The more organised and strong the NSA is, the higher the probability that the situation will be considered an armed conflict,Footnote 236 resulting in the attribution of jus in bello obligations upon the NSA party to the conflict.Footnote 237 A similar line of thought could also be useful in our context in attempting to apply and interpret the state-centric tools of jus ad bellum in complex situations such as the case generated by the Islamic State.
The invocation of a functional approach in the field of occupation law tends to lead to more accountability for an occupant, and more protection for the occupied.Footnote 238 In the context of jus ad bellum, it can also lead to more accountability – both from the sovereign state, which will wish to re-establish its authority in the relevant territory, and from the intervening states, which will be required to analyse in a more nuanced and dynamic fashion the question of unwillingness and inability in different territorial parts of the conflict. As for the invocation of a functional approach in matters of statehood, it places the emphasis on governance Footnote 239 rather than on the traditional Montevideo Criteria,Footnote 240 which illustrate the Westphalian notion of the sovereign state.Footnote 241 As noted earlier, quasi-states tend to be regarded functionally as states if and when the differences between them and states are viewed as irrelevant for the purposes of the legal rule at hand, in light of the nature and function of the legal arrangement in question.Footnote 242 As I will explain, the Islamic State illustrates just when a functional approach is required: when dealing with armed conflicts that include various players and, in particular, NSAs in control of territory over which they exercise governmental functions.
Jus ad bellum firmly reflects a state-centred perceptionFootnote 243 under which states may regulate their domestic affairs without foreign interference,Footnote 244 a main aspect of which is their exclusive right to use force inside their territory.Footnote 245 However, in the present case the Islamic State managed territories and populations in Iraq and Syria for three years – while Iraq and Syria failed to exercise their sovereign authority in the areas under the control of the group. International law might risk being ineffective if it challenges the validity of effective situations by creating a conflict between law and fact.Footnote 246 Accordingly, state-centrism in international law is tempered by the notion of ex factis jus oritur – namely, that effective power cannot be ignored at the risk of rendering redundant legal rules in the face of new reality.Footnote 247 This principle, ex factis jus oritur, is fundamental in that the international legal order, absent a centralised structure, demands a strong and concrete impact on reality in order to solidify its foundations.Footnote 248
There is a limit, though, to the importance granted to effective power and its ability to affect the legal perception of a situation. This limit is encapsulated in the rule of non-recognition, which rejects the legal competence of an illegally created entity,Footnote 249 based on the general principle of ex injuria jus non oritur.Footnote 250 As noted by Lauterpacht,Footnote 251 this rule aims to vindicate the legal character of international law against the law-creating effect of facts. According to the rule of non-recognition, effective power cannot justify infringing the basic pillars of the international system, nor affect state sovereignty in a permanent manner. Nevertheless, effective power and governance, such as that exercised by the Islamic State, invited an interpretative move that recognises the reality on the ground by treating functionally the Islamic State as a state for the sake of jus ad bellum, without permanently infringing the sovereignty of Iraq and Syria.
In my view, it is preferable to face head-on the reality, with creative interpretation of the existing law under the UN Charter, instead of invoking a doctrine without legal status under international law, such as ‘unwilling or unable’, while ignoring completely the reality and particularly the fact that Syria is actually willing and able to fight the Islamic State but not with the intervening states in the US-led coalition. Invocation of a functional approach does not create new law, as the invocation of the doctrine of ‘unwilling or unable’ might have attempted to do; rather, it relies on the existing law (be that self-defence or collective security efforts) by interpreting the situation in accordance with the reality on the ground. Given the high number of players in the Syrian context, the different affiliations and loyalties, and the fact that several of them are in control of a territory, a functional examination is a more logical and appropriate option. Such an approach will help to deal more effectively with the complexity of the situation, bring about more accountability and protection and, most importantly, not undermine the very system it was invoked to protect.
5. The Response of the Security Council in the Campaign Against the Islamic State
The military campaign against the Islamic State has been a real challenge for the international security system, given the need to promote peace and security in areas where a variety of players and interests are at play. Generally, as noted by Weller,Footnote 252 the Security Council may determine which state is the author of an armed attack and which state is the victim,Footnote 253 whether there is a right to use force by a certain state,Footnote 254 or even when the right to use force no longer holds.Footnote 255 However, in our case the Security Council was not able to provide authorisation for the use of force against the Islamic State.
The Security Council has several structural limitations. It does not have a military force as it depends on voluntary contributions of soldiers and funds; it operates under the shadow of the right of veto of its permanent members; it lacks transparency and suffers from misrepresentation on the part of all UN members.Footnote 256 The veto power is probably the most criticised aspect of the work of the Security Council in that it allows the five permanent members of the Council to promote either their own self-interests or those of their allies.Footnote 257 As a result, the effort to adopt a strong resolution as part of the struggle against the Islamic State was blocked by the threat of veto by Russia and China.Footnote 258
On 15 August 2014, soon after the declaration of the establishment of the caliphate by the Islamic State and the Yazidi crisis, the Security Council adopted Resolution 2170.Footnote 259 The raison d’être of the resolution was the Islamic State and the dangers it poses; however, while the use of force against the group was intensifying at that point in time, the resolution did not address the issue at all. Rather, it focused on the phenomenon of foreign fighters joining the Islamic State, calling on UN member states to take national measures to prevent fighters from travelling from their soil to join the Islamic State and other groups in Syria, placing economic sanctions against the group and imposing travel restrictions on six of its members.Footnote 260 In addition, the resolution called for prosecution of foreign fighters, and to prevent ideological extremism.Footnote 261 There was no option to adopt a stronger resolution given the threat of veto from Russia and China.Footnote 262 This is yet a further demonstration of the systemic deficit that the right of veto brings about in the work of the Security Council.Footnote 263
Another important resolution is Security Council Resolution 2249, which called upon states that have the capacity to do so to take all necessary measures to redouble and coordinate their efforts to prevent and suppress terrorist acts committed by ISIL on territory under ISIL control.Footnote 264 Weller suggested that Resolution 2249 can be read as if it relieves particular states from the need to fulfil the criteria for self-defence when considering armed action in Syria.Footnote 265 It seems that the last justification offered by the UK, relying specifically on Resolution 2249, is based on a similar understanding of the resolution.Footnote 266 In my view, the interpretation adopted by the UK is an expansive reading of Resolution 2249. While paragraph 5 calls upon states to take all necessary measures in their fight against the Islamic State, the use of the term ‘calls’ instead of ‘authorises’ or ‘decides’ indicates that the resolution did not intend to grant a legal mandate to act militarily against the organisation but rather to refer to existing lawful measures at the hands of states.Footnote 267 Syria, the most relevant state in the situation, objected to the idea that this resolution provides authorisation to use force on its territory.Footnote 268
As was elaborated above, some of the states operating in Syria do so based on legal claims, particularly the doctrine of ‘unable or unwilling’, which are not clear of doubts. The military campaign against the Islamic State served as a bad precedent in the sense that states might allow themselves to apply an even broader interpretation of Security Council resolutions concerning the use of military force, or simply rely on doctrines which are vague and of unclear legal status – like ‘unwilling or unable’.Footnote 269 The Security Council could have produced a more robust basis by authorising the use of military force under Article 42 of the UN Charter,Footnote 270 yet the effort to adopt a stronger resolution was blocked by the threat of veto by Russia and China.Footnote 271
Another option before the Security Council, which is of relevance to the Syrian civil war and the campaign against the Islamic State, was to invoke the doctrine of responsibility to protect (R2P) – developed under the patronage of the United Nations and applied by the Security Council during the Libya crisis of 2011.Footnote 272 Under this doctrine, considered by SimpsonFootnote 273 and ChimniFootnote 274 as a reconfiguration of humanitarian intervention, if a state is unable or unwilling to stop acts of genocide, war crimes, ethnic cleansing or crimes against humanity occurring on its territory, other states have a collective and subsidiary responsibility to take measures to protect the civilian population.Footnote 275 The United Nations initiative which promoted this doctrine sought to balance between state sovereignty, the pillar of the state-centric system, and between humanitarian needs that arise in conflict situations, such as the current situation in Syria.Footnote 276
This doctrine was invoked during the Libyan civil war in 2011, but while the mandate granted to the North Atlantic Treaty Organization (NATO) by the Security Council was for humanitarian reasons (such as the enforcement of no-fly zones),Footnote 277 NATO broadened the scope of its mission from protection of the civilian population to over-throwing Muammar Gaddafi in a way that tainted this doctrine, which was considered then as an emerging norm of great significance.Footnote 278 Against this backdrop, BRICS nations (Brazil, Russia, India, China and South Africa), which felt betrayed after the Libyan experience, object to any external intervention in Syria that is not based on the UN Charter or on Syria's invitation.Footnote 279 This resistance to external intervention was in spite of the fact that the number of casualties, the grave character of the violations and the intensity of the hostilities are much higher in Syria than was the case in Libya.Footnote 280 In practice, while during the earlier stages of the Syrian crisis some Security Council resolutions acknowledged the responsibility of Syria to protect its population,Footnote 281 the Council never took the additional step of advancing protection under R2P in Syria.
Syria failed to prevent the commission of international crimes on its territory, and in several instances the Syrian government itself committed atrocities, such as the use of chemical weapons.Footnote 282 The Syrian context was a prime case for invoking R2P, yet this option never came to realisation. The misuse of R2P in the context of Libya demonstrated how this doctrine can, and did, serve as a means to justify coercive intervention based on political motives.Footnote 283 As such, these two doctrines – R2P and ‘unable or unwilling’ – can each be seen as an apologetic justification for the use of force. The reasoning behind the invocation of each doctrine might be portrayed differently: R2P was depicted in the Libyan context as an attempt to protect humanitarian interests,Footnote 284 while ‘unwilling or unable’ was invoked against the Islamic State to neutralise a threat.Footnote 285 Still, in practice, the misuse of R2P in the first and only opportunity it was invoked was apologetic in its execution (taking advantage of a noble goal in order to promote political interests). In comparison, the invocation of ‘unwilling or unable’ in Syria was also apologetic as it covered the fact that the states invoking the doctrine ignored the most crucial fact in the application of the doctrine – Syria was indeed willing and able to fight the Islamic State, but simply not in conjunction with the US-led coalition.
While the doctrine of R2P is currently no more than soft law, I believe that its invocation, or its lack thereof, is of theoretical and normative interest. The doctrine challenges the superiority of sovereignty by promoting the view that protection of sovereign states from forcible intervention is conditional, similar to the doctrine of ‘unwilling or unable’. As acknowledged by Crawford,Footnote 286 under R2P a state maintains its full sovereign rights only if it meets its responsibility to its nationals and to other states.Footnote 287 Thus, the invocation of R2P by the Security Council could have affected the direction in which sovereignty will evolve in future years to come, and also serve as a test case for the resilience of the Westphalian orderFootnote 288 and to the possible legal status of this doctrine. While the ICJ recognised in the Nicaragua case that states are permitted to apply proportionate countermeasures which do not amount to a use of force,Footnote 289 such possibility to employ military countermeasures without infringing the prohibition against the use of force was never really specified. Also, today, it is clear from Articles 22 and 50(1)(a) of ARSIWA that international law does not prescribe the use of military force that is outside the purview of the UN Charter, and particularly Articles 2(4) and 2(7) of the Charter.
The limits against individual actions by states demonstrate the important role of the Security Council and, in particular, in the prescription of the legal basis for the deployment of military force in Syria. The fact that R2P was not used in Syria indicates the strength of Syria's sovereignty, along with the lack of political interest in promoting the doctrine, even in spite of a prolonged disastrous conflict on its territory which brought about the death of hundreds of thousands and the injury and displacement of millions. In simple words, it indicates that currently the doctrine of R2P is of no tremendous importance in law or in practice.Footnote 290 In sum, the Security Council did not provide legal authorisation for the campaign against the Islamic State; nor did it advance determinacy, validation, coherence or adherence to the rules of jus ad bellum.Footnote 291 The invocation by states that are using force in Syria of terms which are vague, and of debatable legal validity, reflects gaps in the current legal framework and in the ability of international institutions, especially the Security Council, properly to address challenges to the Westphalian order as that presented by the Islamic State.Footnote 292
6. Conclusion
The Islamic State has transformed itself from a small group into a quasi-state which administers territories, presenting capabilities and wealth like no other group before it. In doing so, it did not seek the acceptance of other players in the international system; rather, it presented itself as a direct challenge and an alternative to the legal and social system underlying today's global order. The international community reacted strongly against the group, with coalitions of historic size and strength. Between 2014 and 2017, intense military operations against the group led to the loss of most of the territory in Iraq and Syria that it used to control and much of its resources. By 2019 the Islamic State had lost all the territories that it had previously held.
As the attempt of the Islamic State to establish a caliphate presented a challenge before the current international legal order and a threat to undermine the ideology underlying it, the campaign against the Islamic State can be seen as a battle for the protection of the international legal system and its core values. The doctrine which justified the use of force in Syria by leading members in the US-led coalition was ‘unwilling or unable’, notwithstanding the fact that it has no root in international law at the present time. Even if this doctrine has acquired a status under international law, as suggested by Scharf, it is not applicable in the present case because Syria was willing and able to fight the Islamic State, as it did with the assistance of Russia and Iran. As a result, the invocation of the doctrine of ‘unable or unwilling’ served as an apologetic justification for the use of force.
The Security Council did not provide authorisation for the use of force against the Islamic State; therefore states protected what they perceived as their national interests, even at the cost of violating international law (in particular, the prohibition against the use of force and the principle of non-intervention). The Security Council could have used the doctrine of R2P, but the failed attempt to invoke the doctrine in Libya cautioned the Council from using it in the context of the civil war in Syria (even though this disastrous conflict brought about the death of hundreds of thousands and the injury and displacement of millions). The doctrine of R2P challenges the superiority of sovereignty, as does the doctrine of ‘unwilling or unable’, but the fact that it was not used in Syria indicates the strength of state sovereignty along with a lack of political interest in promoting the doctrine. Invocation of doctrines such as ‘unwilling or unable’ reflects the gaps in the current state-centred legal framework, and in the ability of international institutions to address challenges such as that presented by the Islamic State.
A possible solution is consideration of a functional approach in the field of jus ad bellum, by analogy with the increasing use of a functional approach in other fields. In simple words, the Islamic State could have been be treated functionally as a state for the purposes of self-defence or collective security measures. This suggestion correlates with the solution of jus in bello to situations in which NSAs exercise effective control over territory. It can also lead to more accountability – from both the sovereign state and the intervening states.
This approach balances two competing interests, which are reflected in principles of international law. On the one hand, there is the need to avoid the risk of ineffectiveness of the law – as effective power cannot be ignored at the risk of rendering redundant legal rules in the face of a new reality (ex factis jus oritur). On the other hand, international law completely rejects the legal competence of an illegally created entity based on the rule of non-recognition and the principle of ex injuria jus non oritur. The functional approach is an interpretative move that recognises the reality on the ground by treating functionally the Islamic State as a state for the sake of jus ad bellum, without infringing permanently the sovereignty of Iraq and Syria. In my view, it is a better option to interpret creatively the existing law instead of invoking a doctrine without legal status under international law while ignoring completely that Syria is in fact willing and able to fight the Islamic State but not in conjunction with the states in the US-led coalition.
