The growing range and changing nature of unilateral sanctions have seen the emergence of a new label of so-called ‘secondary’ sanctions, as opposed to the more traditional ‘primary’ sanctions. While there is no accepted legal definition of secondary sanctions, in essence, secondary sanctions restrict economic transactions between third countries which may be entirely lawful under the law of these countries. Their extraterritorial character gives secondary sanctions their distinctive and particularly controversial character. Secondary sanctions create inter-State tension and may possibly violate a number of public international law regimes. They may harm the politico-economic interests of third States and cause headaches for private economic operators, whose potential exposure to secondary sanctions complicates the already complex web of multi-jurisdictional norms governing their international business transactions.

This chapter explores how the imposition of unprecedented sanctions against Russia following the large-scale invasion of Ukraine in 2022 and the constant cat-and-mouse game of enforcement and evasion that ensued have altered the secondary sanctions landscape. More specifically, it examines to what extent, notwithstanding its longstanding and entrenched opposition to far-reaching US secondary sanctions, the European Union has gradually moved towards adding a ‘secondary’ layer to its own sanctions toolbox. The chapter first exposes the EU’s ambiguity towards extraterritoriality, both within and without the sanctions domain. It subsequently zooms in on a number of specific EU measures, namely the imposition of the so-called ‘price cap’ on Russian oil, the adoption of far-reaching import and export restrictions, including the prohibition to import certain Russian products even after these are located or have already been processed in third countries, and the threat of financial sanctions against, and criminal prosecution of, non-EU persons that facilitate the circumvention of EU sanctions against Russia. It then offers some concluding observations.

This chapter studies the idea that Americans and Europeans hold different views on global security. Generally, it is considered that the EU side demonstrates a stronger adherence to positivism in international law, while the US adopts policy-oriented methodologies. This translates into different views of the actual content of the UN Charter rules on the use of force, for example of the permissibility of self-defense against attacks by non-State actors, calls for new exceptions to the prohibition of the use of force and in relation to controversial issues, such as the legality of the anticipatory self-defense. The chapter offers a critical look at the alleged difference by studying the US-led military coalition fighting against the so-called Islamic State (IS) in Iraq and Syria. This reveals a gradual acceptance of the more expansionist interpretation put forward by the US. Indeed, the case of the US-led military coalition against IS is one where European States - and several other western States - originally steered clear from murky legal grounds only to find themselves ultimately embracing an extensive reading of the right of self-defense, and relying for the first time, whether explicitly or implicitly, on the controversial “unable and unwilling” doctrine to justify military operations abroad.