Blog post: On the illegality of the Turkish offensive in Syria

Published 10 October 2019
By Rebecca Mignot-Mahdavi

On Wednesday 9 October 2019, Turkish President Recep Tayyip Erdogan launched an offensive against both Syrian Kurdish fighters and ISIS terrorists in northeastern Syria. ©Shutterstock, streets of former ISIS capital Al-Rakka. 

In a new blog post, Asser Researcher Rebecca Mignot-Mahdavi debunks the self-defense justification that Turkey uses as its warplanes and artillery strike border towns in north-eastern Syria in a bid to reclaim the region from the formerly US-backed Kurdish forces. “The interpretation of the right of self-defense that would have to be articulated to justify the use of force in this occasion is far from reflecting the still most widely accepted interpretation of Article 51 of the UN Charter.”

On Wednesday 9 October 2019, Turkish President Recep Tayyip Erdogan launched an offensive in north-eastern Syria. Erdogan used an (anticipatory) self-defense narrative, explaining that the offensive will “neutralise terror threats against Turkey” (referring both to Syrian Kurdish fighters and ISIS terrorists) in its broader endeavour in the region, i.e. also in Iraq, to “protect its people from terrorist threats and attacks”.

Turkey has long threatened an attack on Kurdish fighters in Syria, and since US president Trump abruptly announced a complete withdrawal of U.S. troops from northern Syria last Sunday, this long-awaited attack was expected to take place imminently. Observers immediately understood Trump’s announcement as a step made to leave room for a military operation by Turkey. The Trump administration, however, promptly framed the operation as fulfilling the promise to depart from an “endless war” paradigm in Syria.

Identifying and Debunking the Turkish Self-Defense Argument

To find out if the Turkish offensive is legal according to international law, I will focus on their self-defense justification, as Article 51 of the UN Charter is the only legal basis explicitly used by Turkey. Although Turkey remains vague on the actual content of their self-defense argument, we can try to figure out its interpretation of Article 51 by analysing the situation.

First of all, it is essential to underline that the Turkish government does not identify a forthcoming attack from the Kurds in northern Syria against its territory. Rather, it generally refers to the continuous imminent threat posed by hostile groups.

The interpretation of the right of self-defense that would have to be articulated to justify the use of force in this occasion is far from reflecting the still most widely accepted interpretation of Article 51 of the UN Charter.

The Turkish self-defense argument in this case first requires putting forward an extensive version of the ‘accumulation of events doctrine’: in the absence of an identifiable (forthcoming) armed attack, the only interpretative option is to refer to a series of minor incidents which, taken together, can be said to reach the threshold of an armed attack (the accumulation of events doctrine). But this is still not sufficient to match the context at stake.

Turkey’s choice of the right of self-defense to justify its offensive implies to develop the accumulation of events doctrine as follows: action in self-defense against a group can be taken on the basis of past hostile activity from other groups, which somehow share similar interests, and the propensity of the targeted group to carry an analogous hostile intent that could materialize in an armed attack in the future. By justifying its offensive under Article 51, Turkey reveals that it considers possible to deduce a permanent imminence of armed attacks from past events – not even necessarily perpetrated by the targeted group – that show the continuous hostile intent of the group.

As an effect of this extensive interpretation of the subject-matter limitation of the right of self-defense, the Turkish self-defense argument also requires arguing for an extension of the temporal limitation of the right. Indeed, the self-defense justification in this case implies that even without any concrete indication that attacks will actually occur, force is used to prevent a prospective threat from becoming imminent. This is preventive self-defense.

This set of arguments is simply too far from the accepted interpretation of the law on self-defense. To a certain extent, Turkey’s (implicit) self-defense argument echoes the chain of propositions that states like the US, UK, Australia, and France have articulated or at least partially endorsed on the question of how to interpret the right of self-defense against terrorists. However, this chain of propositions is still highly contested, even when it concerns jihadist terrorist groups.

Silence and the Use of Force in International Law

Until now, very few states have been vocal on the illegality of the Turkish offensive under Article 51 of the UN Charter. On Tuesday 8 October, European Commission President Jean-Claude Juncker called Turkey to show restraint in a speech to the European Parliament. On Wednesday 9 October, the High Representative Federica Mogherini called upon Turkey to cease unilateral military action and issued a declaration in that sense on behalf of the EU. None of them explicitly referred to the illegality of the operation, nor rejected Turkey’s interpretation of the right to self-defense to justify its military offensive.

Germany, Britain, France and Canada, in separate statements, were first in expressing concern and/or strongly condemning the military operation, sometimes briefly referring to the necessary respect of international obligations. But they mainly insisted on the risk of destabilising the region further and undermining the progress made against ISIS in the region.  On Thursday, the Security Council, meeting at the request of Germany, France, the UK, Belgium, and Poland, failed to agree on a joint statement condemning the attack.

To my knowledge, besides the obvious protest from Syria itself, only two states formulated legal arguments against the Turkish offensive. Liechtenstein (in line with a tradition of promoting a coherent and non-extensive interpretation of the right of self-defense) expressed concern for leaving unchecked “overly broad” interpretations of Article 51 of the UN Charter and undermining the “rule-based order we all rely on for peace and security”. Greece also denounced on Thursday evening the illegality of the operations under international law.

Beyond the strategic concerns regarding the negative impact that the offensive could have on ISIS development in the region, this is a crucial occasion for states to express views on the extensive interpretation of the right of self-defense proposed by Turkey.

By Rebecca Mignot-Mahdavi.

Rebecca Mignot-Mahdavi LL.M is part of the Asser research strand Human Dignity and Human Security in International and European Law. This research strand adopts a human rights approach to global challenges in the field of counter-terrorism, international criminal law, international humanitarian law, international trade, environmental protection, European private international law, and the law of EU external relations. It examines what it means to safeguard human dignity - also in relation to human security - in these areas.

Further reading
Countering terrorism through the stripping of citizenship: ineffective and counterproductive
In this perspective, Dr Christophe Paulussen examines the scope and nature of citizenship stripping as a counter-terrorism measure and argues that it stands out in comparison to other counter-terrorism measures. This is because of its highly symbolic nature, its far-reaching effects, as well as its emphasis on ‘addressing’ the problem by making it the problem of other states. (ICCT Perspective, 2018)

Should Europe uphold the right to return even for Daesh families? 
European powers are yet to claim their citizens, who want to return home from former Daesh-held territories in Syria, posing a significant question over whether the legal principle of the right to return will be applied. An interview in TRT World, featuring Dr Christophe Paulussen.

Asser International Crimes Database
The International Crimes Database offers an extensive online collection of international crimes broadly defined, such as genocide, war crimes, terrorism and piracy. It provides access to a range of information, not just for scholars and practitioners (such as judges, prosecutors and defense counsel), but also for students, journalists, families and communities of victims of crimes. It also contains a specific tab dealing with cases of foreign fighters.