International law prohibits States from intervening in the internal and external affairs of other States, but only if the method of intervention is coercive. Building on recent developments in State practice, especially in the cyber context, this 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 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
