On Attacks Against Missions Abroad and Whether International Lawyers Really Ought to Be Zoologists: A Rejoinder to Tom Ruys

In Beyond Tehran and Nairobi: Can Attacks against Embassies Serve as a Basis for the Invocation of Self-defence? we have argued that both the empirical analysis of more than 730 incidents and the review of jurisprudence suggest the unlawfulness of invoking self-defence in response to attacks against diplomatic and consular missions.

We are grateful to Tom Ruys, who has raised several important points challenging our methodology and some of our findings in his witty and sophisticated Reply. In our Rejoinder, we will address three main issues in response to his criticism. First, the fact that almost all attacks against missions emanate from non-state actors and are small-scale in nature (the appraisal of ‘pink elephants’). Second, the alleged paradigm-changing role of certain ‘black swan’ events. Finally, we will test the implications of Ruys’ policy argument for the jus contra bellum system.

1) Of pink elephants – the appraisal of allegedly unprecedented events missing from our research

Ruys voices two concerns about our method of identifying the customary rules on the use of force and illustrates them with two catchphrases: pink elephants and black swans. By the former, he describes a situation where an attack happens in unprecedented circumstances, such as, ‘to put in it the absurd’, against a pink elephant, as ‘States have never claimed the right of self-defence in response to attacks against (State-owned) elephants’.

First, Ruys asserts that the examples analysed in our article are not really relevant regarding the question of self-defence, as ‘one is hard pressed to identify even a single instance of an intentional attack of some gravity by one State against an embassy of another State outside the context of an ongoing armed conflict’; therefore, the typical prerequisites for an armed attack are not present. Our article also acknowledged this caveat about the overwhelming majority of incidents; however, we believe that Ruys both downplays the relevance of the legal context of Article 51, and what inferences can be drawn from existing state practice.

Although theory in itself does not give a conclusive answer to the question whether attacks against missions can be regarded as armed attacks in the sense of Article 51, we nevertheless think that the possibility to use force to protect an embassy or consulate abroad should not be appraised in a legal vacuum. We fully subscribe to the position that Ruys advocates in his 2017 article regarding the scope of Article 2(4), namely, that ‘… the origin, object, and preparatory work of Article 2(4) suggest that its scope should be understood broadly. The burden of proof would therefore seem to rest on those advocating a more restrictive interpretation.’ Consequently, ‘Absent” express authority” on the matter… it is they who must provide relevant evidence from customary practice to support their views.’ We also share his opinion formulated in his monograph ‘that Article 51 UN Charter – whether considered an exception or a supplement to Article 2(4) – is inextricably linked to the Charter prohibition on the use of force’.

If one accepts both findings, it is difficult to see how the burden of proof would not rest on those advocating a broader interpretation of Article 51, as this would automatically narrow the scope of Article 2(4). This allocation of the burden of proof is also in line with the general principle of onus probandi actori incumbit, as the state using force to protect its mission would be required to prove that it did not violate Article 2(4) in all legal disputes; thus, that it acted in lawful self-defence under Article 51. As such, in our opinion, as international law stands today, the list of potential targets against which attacks may result in the rightful invocation of self-defence has its limits, as has been evidenced by state practice since the adoption of the UN Charter. In the field of jus contra bellum, everything is prohibited except what is (had been proved to be) permitted.

Second, in Ruys’ view, although we have highlighted attributable and grave incidents, our research misses the most relevant forms of attacks, where these requirements are clearly met. However, we believe that the relevance of these otherwise essential criteria is mitigated by the fact that most attacks have occurred against states whose practice clearly do not deem these requirements to be necessary elements of invoking the right to self-defence. Notably, as the US has underlined in its Rejoinder to the Oil Platforms case: ‘Article 51 of the UN Charter contains no qualifications regarding the size of “armed attacks”’. This suggests that the lack of these criteria in specific incidences would not hinder these states in claiming self-defence in the event of mission attacks as well. In our view, the absence of such a characterisation is relevant evidence of a negative opinio juris in this respect.

Finally, it should be also noted that smaller-scale attacks against possible targets of an ‘armed attack’ are usually interpreted as less grave forms of use of force, whilst attacks against missions are consistently treated within the ambit of diplomatic law or as criminal incidents. Tellingly, even the East Africa bombings, which resulted in the death of hundreds and injury to thousands, were treated as such by the Security Council itself in Resolution 1189.

2) Of black swans – The alleged paradigm-changing role of unprecedented events

By black swans, Ruys refers to a problem originally posed by Karl Popper about paradigm-changing events, such as the discovery of the black swans of Australia, which destroyed the European belief that all swans were white. In Ruys’ view, we analysed more than 700 cases in vain as:

‘the absence of State involvement in addition to the mostly small-scale nature – it is, however, doubtful whether these cases […] tell us much about the ‘black swan’ scenario, being that of a deliberate large-scale attack by one State against another State’s embassy (outside of an existing armed conflict).’

However, Ruys’ example ignores an important distinction between social sciences and natural sciences, a distinction which was relevant for Popper’s research as well. In natural sciences, facts and norms are existing circumstances (this is the realm of ‘Sein’), awaiting to be discovered by researchers, therefore the discovery of something radically different (such as a black swan) can naturally bring down the pre-existing paradigm with retrospective effect. Importantly, the discovery of black swans not only demonstrates that not all swans are white, but also that non-white swans had been existed for quite some time, debunking the paradigm with ex tunc effect. In contrast, law is a social construct, which does not describe what exists, but determines what is ought to be (by creating the realm of ‘Sollen’). Therefore, the rules of international law, as opposed to laws of natural science, are not ‘hidden’ and waiting to be unveiled, but are created and changed in a dynamic process by the behaviour of their subjects.

To borrow a phrase from Ruys’ Reply, establishing customary rules ‘is not an exercise in exact science’, as a single incident contrary to existing norms cannot by itself change the law, even if it may be the first step towards such a change. The concept of paradigm-changing ‘Grotian moments’ (which was espoused by Michael Scharf) is far from being universally accepted. Be that as it may, Ruys’ black swan analogy in the context of jus contra bellum claims no less than that a rare event in the unforeseeable future will retrospectively define the content of a legal rule. In other words, Ruys’ approach leaves us with evaluating the legality of a future event based on legal rules that were created by (or re-interpreted based on) the very same event.

We believe that such a methodology risks weakening the normativity of IL and the jus contra bellum system in particular. How could a norm fulfil its normative mandate of regulating future conduct if the obligations stipulated by it can be determined or even rewritten substantially by the very event it should regulate? Admittedly, no rule in international law enjoys immunity from change, as the unique logic of international law permits that violations of rules could lead to the formation of new ones. However, we think that waiting for the black swan to ascertain the scope of a norm instead of aiming to establish the current state of law based on the analysis of state practice seems to offer too narrow a reading of an international lawyer’s task.

As a final note, let us imagine the alleged black swan event in the present context. In the case of an attributable, large scale attack against an embassy it is most likely that states would react as they usually do in similar situations. They would express sympathy and moral support for the victim without elaborating on the legal characterization of the response (i.e. any clear opinio juris). Thus, we would still face the task of evaluating the lawfulness of the operation with the same set of knowledge we have today. Put it bluntly, contrary to natural science, (international) law has no black swans; it has at best swans the colour of which is always a matter of legal evaluation.

3) Testing Ruys’ policy argument and its implications for the jus contra bellum system

Ruys ‘plays the devil’s advocate’ when he asks whether we really believe that, if a large-scale intentional airstrike by State A were to occur against the embassy of State B (with the consent of its host State C), ‘such attack would not be seen as an ‘armed attack’?’ Furthermore, he asks whether it would not drive us to the conclusion that attacks against missions ‘are not automatically excluded from the purview of Article 51 UN Charter’?

Regarding the first question, we share Ruys’ concern that a large-scale, attributable attack will not be left without a response. However, we believe that a distinction ought to be made between what is ‘seen’ by the victim state and what really ‘is’ an armed attack. In exceptional circumstances, even the use of force by the sending state could be seen as a legitimate action; this however would not make it legal. Readers will be familiar with unlawful actions that were nevertheless deemed legitimate by the international community, such as the humanitarian intervention in Kosovo and the Entebbe mission seeking to protect nationals abroad. For the same reasons as with Entebbe (see here and here) and Kosovo (see here and here), our scenario would not be unpreferred from a policy perspective either, whereas the opposite approach offered by Ruys seems to open Pandora’s Box. What Ruys apparently suggests is that it is compatible with the system of Articles 2(4) and 51 to say that there are infinite emanations of a state in the self-defence sense (i.e., we are surrounded everywhere by pink elephants, red rhinos, purple zebras, turquoise giraffes etc.) and that these could be discovered at any minute and, having a profound impact on the law as it is or even on what it was before.

Importantly, the outcome of our research does not suggest that states are left without any means to respond to attacks against their missions. These possible measures, however, fall under criminal law or diplomatic law, alongside related rules on state responsibility, and, as ultima ratio, under the authorisation of the Security Council. The latter does not mean that the response would be unduly late or ineffective neither. For instance, in the case of the 1999 Chinese embassy bombing in Belgrade, the SC met for its 4000^th meeting at 3:40 AM, a few hours after the bombing. In comparison, as we have shown in our article, it always took at least several weeks (or even years) for the US to respond in “self-defence” to mission attacks. Moreover, we have already witnessed that the SC is willing to take binding resolutions under Chapter VII to protect missions, such as Resolution 667, in response to the Iraqi attack on missions during its invasion of Kuwait.

As to Ruys’ argument concerning the automatic exclusion of missions from the possible targets of armed attacks, we believe that there are no a priori principles in the use of force, as it builds upon the rules and practice of the international community. Therefore, we cannot deem any targets in abstracto to be excluded from the purview of armed attacks, as it is subject to the ever-evolving body of customary law. What we can do, however, is to analyse the practice of states in the light of the wider legal context and background, i.e., the system of Articles 2(4) and 51. If we perform this exercise, we can observe that there exists a general prohibition on the use of force and that until now states have consistently treated mission attacks as outside the regime of the use of force. Consequently, it is no exaggeration to say that mission attacks in the current state of international law do not give rise to the right of self-defence. Needless to say, this stance could be changed over time by widespread and constant practice of the members of the international community. Nevertheless, we find it as an important role of international lawyers to highlight the state of affairs to provide governmental stakeholders with a landscape of the current practice – and, for such a safari, advisers do not even have to be zoologists.