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Overextension of “Self-defence”- Turkey’s military actions in Syria a Continued Cause of Concern

- Aditya Kaushik and Aayushi Gupta


The ongoing war in Eastern Europe has diverted the global public attention away from another hotspot of manmade human disaster, Syria. The Arab Springs rebellions of early 2010, and the subsequent rise of the Islamic State plunged the Syrian state into a prolonged humanitarian crisis. The same also opened opportunities for major powers such as the United States, Russia, European states, Iran, Turkey etc, to interfere in the Syrian Game of Thrones, either directly or via proxies.

In this context, Turkish activities in Syria should come under growing international scrutiny due to their multi-dimensional impact on the life of the Syrian people, and also due to the alleged violations of jus ad bellum, and International Humanitarian Law. Since 2016, the Turkish military has intervened in Northern Syria 4 times (four formal military operations have been conducted), apart from the activities of the pro-Turkish rebel groups (Syrian National Army) which have been active in the country from the onset of the conflict.

These operations along with the activities of the aided and associated groups have allowed the Turkish state to gain direct or indirect control over 8,835-square-kilometre of Syrian territory. Undeterred due to lack of consistent criticism, the Turkish President has time and again threatened to expand this so-called buffer zone to 32 Km, thus, driving away Syrian Democratic Forces (“SDF”) (a rebel group in Syria fighting for Kurdish autonomy), and creating a space for illegal refoulement of the refugees. Not only do these actions significantly impact the rights of the individuals living in these areas, but they also directly infringe upon the Syrian state's sovereignty.

In this context, it becomes pertinent to analyse the legality of such operations under the touchstone of international law regarding self-defence and use of force as enshrined under the United Nations Charter (“Charter”), as well as Customary International Law.

Legal Framework

The United Nations came into existence with the stated purpose of maintaining international peace and security and suppressing acts of aggression. Thus, establishing rule of law among nations. National power continued to remain a decisive factor in international relations to the extent that military strength continued to shape alliances, and deter aggression, however, the legitimacy attributed to the "use of force" or war as a means of state practice was withdrawn by the express bar provided under the Article 2(4) of the Charter.

Article 2(4) of the Charter prohibits the use of force against member states, whereas, Article 51 provides for an exception to the said rule in case of armed attack. The article has been subject to intense debate as it saves the customary right of self-defence inherent to every state, furthermore, unlike Article 2(4) it omits the mention of terms such as "members" or "state". Leaving it open for both restrictive and expansive interpretation. This has caused multiple issues regarding the definition of the use term "armed aggression", "use of force", and the application of the right to self-defence in the case of non-state actors.

Firstly, for this article, the author would be assuming that the right to self-defence exists against non-state actors (mainly terrorists), in light of the changes in the legal duties of states post Resolution 1368 and 1373 of the United Nations Security Council, which identified terrorism as a threat to international peace. Furthermore, as the author proposes to recommend changes in Indian foreign policy concerning the Turkish actions in India, it is essential to accept for that limited purpose that such right exists as the same has been recognised by the Indian government.

Secondly, the International Court of Justice has identified armed attacks or aggression both by state and non-state actors to be distinct from the mere use of force. The armed attack has been recognised as the application of the highest level of force. In the Oil Platform case the court while discussing the intensity of the attack required to be classified as 'armed' reiterated the need to show the scope and intensity to meet the high threshold required to trigger self-defence under the said article.

Some scholars have argued that such a threshold should be lower in case of terrorist attacks in light of the changes in state practice after 9/11. However, the author believes that such an interpretation coupled with the growing acceptance of the right to self-defence to deal with terrorists independent of the attribution requirement stated in the Congo v Uganda case (or the one provided under the draft articles on State Responsibility presented by the ILO would open the doors for excessive utilisation of such ground by the stronger states to interfere in the affairs of states allegedly housing the groups perpetrating certain acts of violence in neighbouring other countries. This can be detrimental both for global peace and the right of the Global South (for example, US intervention in Afghanistan), and can reverse the gains made due to the establishment of the UN. Thus, in the author's view, the position taken by the ICJ remains the correct interpretation of the law of self-defence.

Regardless, of whether an attack can be classified as an armed attack or not, any response should necessary and proportionate. An action which lacks proportionality is considered an armed reprisal that is considered illegal in the Post-UN law.

Turkish Actions on the Touchstone of International Law

Since the late 1970s, Turkey has time and again carried out military operations inside Syria and Iraq to deal with the threat posed by the Kurdistan Workers’ Party (“PKK”) which Turkey has labelled as a terrorist outfit. While some nations have time and again voiced their concerns against the such blatant violation of the latter two countries sovereignty, the developed world has tacitly accepted them due to geopolitical reasons. Some of these limited measures could have been excused where the threat is imminent or instant and overwhelming under Customary International Law. The same cannot be said for the operations that have been carried out since 2016, as not only they have led to the mass displacement of the native Syrian population but have also led to Turkey gaining effective control of part of Syrian territory.

Such an occupation (the author uses the term very carefully), in the name of self-defence, would require Turkey to prove that not only Turkey has suffered 'armed attack or aggression' from groups operating in these territories but that future attacks are imminent. Furthermore, it has to prove that actions are proportionate and essential to deter future aggression.

The Turkish government claims that the Syrian Democratic Forces, Democratic Union Party and its militant branch People's Protection Units (“YPG”) which gained large parts of Syria bordering Turkey during the civil war, are the same or working with PKK to destabilise the southern region of Syria (which remains Kurdish dominated). Thus, the Turkish argument is that YPG is responsible for the multiple disruptive acts committed by PKK. The mere presence of a common objective in itself cannot make one organisation synonymous with the other; concrete proof must be provided to prove non-distinctness in existence and function. Otherwise, the states will have the excuse to invade all the territories where groups with ideologies similar to the one they identify as hostile. Turkey has been unable to even convince its own NATO allies of this view with both European Union, and the United States recognising YPG and PKK as distinct entities. Therefore, the very act of attributing one’s action to the other remains in serious doubt.

Prime facie acceptance of the above-mentioned claim by Turkey does not go a long way in aiding its cause. The occurrence of an armed attack or imminent is essential to justify the claim of an armed attack. As noted earlier, the threshold for the same is by design quite high to forestall misadventures by powerful states. While the initial operation (Operation Euphrates) in 2016 can draw its legitimacy from the UN Resolutions asking for the states to take coordinated actions for dealing with ISIS, the subsequent actions and operations of the Turkish states cannot be said to be covered under the said protection, as there stated purpose is to primarily deal with Kurdish entities. Turkey has argued that those operations and other military actions have continued in response to multiple acts carried out by PKK after the ceasefire in 2015 ended.

Turkey has maintained that these activities accumulated together would constitute an armed attack, and therefore, would merit a response in self-defence. There are multiple issues with this argument, the Congo v Uganda case where ICJ has said to accept the doctrine of accumulation did not deal with that issue directly. It was only in a hypothetical that ICJ in its obiter referred to such a possibility. The right was also denied to Israel in the case of the Wall case. The doctrine also has multiple logical contradictions, it does not provide for a timeline on which accumulation can be said to have happened. Similarly, where a country has already taken in response to such issues, the question of whether or not they would still be considered for accumulation remains open to debate. Furthermore, some of these attacks might not have any direct relation with the individuals in Syria i.e., they are completely domestic actions. Moreover, the 2018 rocket attacks that have been cited by Turkey to justify the operation Olive Branch (2018) as a direct provocation happened after said Turkish operation in Syria. Thus, as per Peters the same cannot be used as an excuse to justify past actions including the continued occupation.

These two operations were followed by another major offensive titled Operation Olive branch. The letter was justified because PKK/YDK nexus has been smuggling arms and firing ammunition on Turkish posts. However, no further substantiation has been provided by Turkey in its letter to UNSC. Researchers have attempted to justify these acts but they have all struggled to accept the occurrence of any armed attack to justify such operations by Turkey in absence of credible evidence. Even if these activities by the fights Operation Olive Branch drove away large numbers of people that Turkish forces considered as unwanted (read Kurds) from the affected area.

Turkey has also implicitly taken recourse to the doctrine of unwilling and unable, to justify its claimed first responder rights in these situations. The doctrine gives the right to the victim of an armed attack by private groups to take action against such groups if there is evidence to believe that the home state lacks the will or ability to deal with such entities. The fact that the Syrian government does not control all the territories recognised as the territory of the Syrian state is a fact, they also lack any form of control over the Kurdish fighters.

Disregarding the fact that the doctrine itself has not been accepted as a part of Customary International Law by many states, Turkey still should not be given any benefit of the same. As its actions of supporting certain rebel groups and even taking direct military action to stall Syrian military advances in the Northern Syrian regions have been instrumental in rendering the Asa’ad regime incapable of administering its territory.

States which indulge directly to undermine or overthrow the UN-recognised government cannot be given then is given the advantage of a troubled government's inability to take action against certain groups. This would not only be rewarding the intervening state benefit of its wrong but also because the precedent it would set is very worrisome, as it would provide a loophole for other states to first ferment chaos and then take control of lands owned by other states. Thus, till the point Turkey continues to play a role in restraining the Syrian government in Syria, it cannot be granted the right to take recourse to this troubling doctrine.

Necessity and Proportionality

Even if the aforementioned arguments are considered as valid, they will not save any action from attracting illegality if such actions do not qualify the test of necessity and proportionality with minimal collateral damage. Necessity as per the Caroline case means threat which is “instant, overwhelming and leaving no other choice of means and no moment of deliberation". The conventional position has long limited the scope of the International Law of self-defence to "anticipatory or imminent" threats, and not threats that state(s) concoct in hypothetical (pre-emptive/ Bush Doctrine in Afghanistan has been widely condemned).

Turkey has used both "continued" and "imminent" in its letter submitted to UNSC. 'Continued' as per scholars entail some assessment of threat which has a probability of happening in the future but not any present existence of threat (pre-emptive), whereas "imminent" is used to refer to the existence of threat which is presently persisting and therefore, requires immediate action. Turkey already controls huge parts of Syria which are adjunct to its borders, it has expelled 'unwanted' entities from these regions, therefore, has no imminent threat on its soil however, and it continues to expand the chance of Turkish military encountering threats would increase. Thus, actions leading from mere pre-emption cannot be justified.

Proportionality can be interpreted in two distinct ways, first, it can mean "corresponding in force or strength in terms of casualty and collateral damage caused”, or “minimal action required to achieve the stated objectives such as 'elimination of threat' or 'halting or repelling danger'". Turkish actions appear to be highly disproportionate when examined based on quantitative proportionality, as it has led to a mass exodus of more than 180,000 people, with casualties from both sides. Accounting for the fact that Operation Olive Branch was justified on some small skirmishes on the border, it is evident that launching such an operation itself was illegal. The situation becomes even more concerning due to the continued occupation of the concerned region by Turkey. An occupation is a major act, which leads to continuous violation of other states' sovereignty till the time occupation subsists.

Such an action would further raise the threshold of proportionality, as provided by the ICJ in the Uganda v Congo case, where it denied the legitimacy of the occupation of Congo by Uganda because some irregulars have carried out armed attacks on Ugandan soil. Similarly, the continued occupation by Turkey is wholly disproportionate.

The qualitative approach also does not justify the continued occupation, or previous actions, as Turkey has taken those actions in pre-emption and not in anticipation of threat. It has also stated that such occupation is not merely for self-defence but also to create a zone to transfer the refugees (a case can be made for its illegality), however, such an excuse cannot be used to justify the use of force, as neither the Customary International Law nor Article 51 provides any scope for the same. It has also been argued by some well-meaning scholars that Turkey has been effectuating the process of Turkification of the occupied region, and has been attempting to gain institutional control of these regions at a huge human cost. The author also believes that such actions are a precursor to the absorption of these regions under the Turkish sphere of influence permanently.


No major threat has originated against Turkey that might lead us to conclude that the proposed operation is anyways more legitimate than the previous action. It is merely aimed at supplementing wrongs committed in the past few years. Strategically it might be sound for Turkey to take such action, it may also help some leaders domestically, but that does not entail legality and legitimacy. Any further military actions by Turkey would not only be unjustified by also illegal.

India has a vested interest in shaping the law of self-defence in a manner that provides us with the legal right to flexibly respond to terrorist actions. However, it does not mean that we should support unjustified, unnecessary, and disproportionate use of armed force in a manner that infringes on other states' sovereignty. It becomes even more alarming when the violator is in many aspects a hostile power. Therefore, the author believes that the Indian government should raise this issue in relevant forums to draw the required attention towards the plight of Kurdish actions.