Revisiting Coercion

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The prohibition of intervention, requiring States to refrain from coercively interfering in the internal or external affairs of other States, is widely recognized as a cardinal rule of customary international law. There is also widespread agreement about the constituent elements of the rule: (1) an interference with a State’s internal or external affairs which is (2) coercive in character. As authoritatively interpreted by the International Court of Justice in the Nicaragua case (para. 205), the principle of non-intervention:

forbids all States or groups of States to intervene directly or indirectly in internal or external affairs of other States. A prohibited intervention must accordingly be one bearing on matters in which each State is permitted, by the principle of State sovereignty, to decide freely. One of these is the choice of a political, economic, social and cultural system, and the formulation of foreign policy. Intervention is wrongful when it uses methods of coercion in regard to such choices, which must remain free ones. The element of coercion, which defines, and indeed forms the very essence of, prohibited intervention, is particularly obvious in the case of an intervention which uses force […]

While the existence and authority of the customary rule prohibiting intervention is not today challenged by any State, the content and application of this rule have been disputed since its inception. This is particularly the case with the element of coercion. Even though the ICJ regarded coercion as the “very essence” of prohibited intervention, it did not define it. Nor have scholars or States otherwise managed to agree on a definition. Almost forty years after Nicaragua, “the scope of coercion for purposes of prohibited intervention remains particularly undertheorized and underdeveloped,” as Caroline Krass, the General Counsel of the U.S. Department of Defense, rightly noted in a recent speech.

I recently finished a (lengthy) article attempting to clarify the notion of coercion, which will be published in the American Journal of International Law later this year; a draft is available here on SSRN, and any comments by readers are very welcome.

Building on recent developments in State practice, especially in the cyber context, the article argues that coercion can be understood in two different ways or models. First, as coercion-as-extortion, a demand coupled with a threat of harm or the infliction of harm, done to extract some kind of concession from the victim State – in other words, an act targeting the victim State’s will or decision-making calculus. Second, as coercion-as-control, an act depriving the victim State of its ability to control its sovereign choices. The two models are complementary rather than exclusive, but they should not be conflated.

The article argues that many of the difficulties surrounding the notion of coercion arise as a consequence of failing to distinguish between these two different models. Coercion-as-extortion consists of imposing costs on the victim State, so as to cause it to change its policy choices. This is precisely how coercion has traditionally been understood in this context, as “dictatorial” intervention. Coercion-as-control, by contrast, is not about affecting the victim State’s decision-making calculus – the victim State’s leadership may even be entirely unaware of the actions taken against it – but consists of a material constraint on its ability to pursue the choices that it wanted to pursue. Consider here, for example, a cyber operation against the elections in another country, which may be entirely unrelated to any demands or threats by the coercing State.

In developing these two models of coercion the article extensively discusses the role of intention in coercion and the possible approaches to conceptualizing the threshold of harm. It also explains how debates on coercion in the non-intervention context have been shaped by the problem of justification. On one hand there is an intuition that some forms of coercion are justified. On the other hand, the prohibition of intervention is regarded as a categorical rule admitting of no exceptions. This incentivizes approaches that narrow down the scope of prohibited intervention, e.g. through the exclusion of economic measures from the concept of coercion. The article cautions against such moralized conceptions of coercion, arguing that the reserved domain element of prohibited intervention is a better vehicle for accommodating problems of justification. In particular, coercive measures taken to enforce compliance with prior international legal obligations generally cannot constitute prohibited intervention in the internal or external affairs of the target State, although they may violate other rules of international law.

One possible response to my overarching argument would be that coercion should not be regarded as a constituent element of prohibited intervention at all, partly because it may be impossible to come up with a principled approach to defining it. Pragmatically that seems an unlikely direction of travel. States recently coming out with their formal positions on the application of the prohibition of intervention to cyberspace have all mentioned coercion as an essential element of intervention, often relying on the ICJ’s Nicaragua judgment as an authoritative restatement of that principle. For example, Ireland did just that only a few days ago, in its new position paper on the application of international law in cyberspace (para. 8). Not a single State has (at least so far) argued in favor of abandoning the coercion requirement, even in some limited category of cases. Discarding coercion for some superior alternative (even if one existed) therefore does not seem feasible, although such an option may become more plausible if States start endorsing it. I frankly very much doubt that any effort of abandoning coercion as an element of intervention would either be useful or worth the political and legal fight and capital that would need to be expended – compare here usefully the UK’s unsuccessful normative entrepreneurship regarding sovereignty in cyberspace. Nor is doing this necessary, since the two models of coercion can, if interpreted reasonably and coherently, do all the work that the non-intervention rule needs to do.

As a matter of policy, I would suggest that, in going forward and when expressing their opinio juris, States could usefully address three sets of issues in any future statements on the non-intervention rule, whether in the cyber context or outside it. First, they should clearly distinguish between coercion-as-extortion and coercion-as-control, while affirming the validity and complementarity of the two models of coercion. Second, they should clarify their approach to the threshold of harm in either model. Third, they should also clarify the nature and role of intention in defining coercion. In that regard, while statements mentioning specific examples of prohibited intervention, such as different forms of election interference, are very useful, it would be even more useful for States to elaborate on why any particular examples are regarded as constituting coercion (cf. the Irish position paper mentioned above, para. 9 (arguing with no further explanation that “malicious cyber-operations seriously compromising healthcare systems or national elections are capable of amounting to unlawful interventions.”) I have explained in the article what the plausible options on these issues questions are, but it is ultimately only States that can clarify the non-intervention rule further, and today there are ample opportunities to do so.

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Douglas Wilson says

July 17, 2023

Thanks Marko. This article is essential reading for those interested in the practice of international law, especially in respect of cyber or covert operations.

Incidentally, I am now going to adopt the phrase "normative entrepreneur", albeit I might leave the evaluation to a later date.

Doug Wilson

Asher Rottenberg says

July 19, 2023

Thank you, Marko.

I apologize for my rudeness, asking before reading the whole piece (The 77-page article is on my "long articles" reading list, which keeps growing thicker every day): Is it your position that non-intervention is a principal doctrine, with little domain-specific adjustments? Alternatively, do you think the doctrine itself might have a different formulation, including the interesting components you just described, depending on the domain? In other words, can we learn from cyber-related states' positions on intervention in general and vice versa? This question arises now concerning due diligence (in the context of environmental law and climate change, which can be extracted from different submissions to ITLOS case no. 31 docket). However, I am wondering whether, in your opinion, this is relevant to intervention, which is an older, yet similarly unexplored concept compared to due diligence.


Marko Milanovic says

July 19, 2023

Thank you for the comment Asher. My position is that non-intervention is a general rule, with the same elements in the cyber domain as outside it.