Katselli Proukaki explores the question of legality of ‘solidarity measures’ in the form of countermeasures, in cases where they are exercised by non-injured States in response to violations of obligations owed to the international community as a whole. This was a controversial issue during the deliberations of the International Law Commission (ILC), and article 54 of the ILC final articles on State Responsibility provides that non-injured States can only take ‘lawful measures’ (retorsion), rather than countermeasures, against the State that violates community interests. The Commentary of the Commission characterized State practice on this subject as ‘limited and rather embryonic’.

Katselli Proukaki attacks the ILC standpoint with good arguments. She stresses that, despite the abandonment of the distinction between crimes and delicts (article 19 of the 1996 draft articles), the ILC maintained the differentiation between simple breaches of international legal obligations, and serious breaches of peremptory norms (Chapter 2 of the book). She argues that the ILC created an enforcement deficit for community interests, and that article 54 does not prohibit the exercise of countermeasures by non-injured States, but rather leaves the matter open to further developments and decisions. Katselli Proukaki's main argument, that occupies the most extensive part of the book (Chapter 3), is that, contrary to the ILC standpoint, there is good evidence that a customary norm permitting the exercise of countermeasures by non-injured States has emerged on the basis of international practice (p 92). She explores the response to violations of community interests by distinguishing countermeasures from State action not amounting to countermeasures, though the distinction is not always clear.

Katselli Proukaki deals also with the question of fragmentation of international law including the relationship between exercise of countermeasures and self-contained regimes (Chapter 4). She favours an extensive interpretation of the ‘right to countermeasures’, and argues that the normative closure of these regimes is relative; she maintains that solidarity measures have a role to play in the EU, WTO, and human rights systems. Furthermore, Katselli Proukaki contends that countermeasures for the violation of norms protecting community interests prevail over the rules of self-contained regimes, even in cases where the regime has structured a complex compulsory dispute settlement system, such as the one established by the WTO Dispute Settlement Understanding (DSU). In the last part of the book, the author explores proportionality as a legal constraint on the exercise of countermeasures (Chapter 5).

The book deals with a problematic aspect of the ILC final articles; the author convincingly demonstrates that the State practice on solidarity measures is not as ‘embryonic’ as the Commission asserted. Katselli Proukaki's core conclusion that countermeasures as solidarity measures are permitted by international law is well-founded, is supported by her research in State practice, and should be embraced.

Nonetheless, the overall analysis does not adequately consider some of the ambiguities and complexities of the subject. Katselli Proukaki challenges the pluralist–realist approach of the ILC on the question of solidarity measures by adopting a purely solidarist counter-interpretation of international law. The difficulty with her approach is that it assumes a deeper consensus on values and policies than actually exists in the international community. The reality is that in a deeply conflict-laden world society shared values are thicker on a regional than on a global level, and this is mirrored, inter alia, in the debate on the so-called ‘clash of civilizations’. It is thus necessary to move beyond the pluralism/solidarism debate towards the concept of global governance, and take properly into account broader systemic interests and structures (cf Hurrell, On Global Governance, OUP 2007, Part I, in particular 95 ff.).

Debate and critique of the ‘policies of international law’ should focus on the negative externalities of solidarity measures, in particular on the direct threat to trade regimes. This risk is intimately linked to the unavoidable politicization of such measures, which may create distortions of trade patterns and destabilize world trade as one of the pillars of globalization. There is strong motivation for States to exercise countermeasures against States considered as unfriendly, and dress them as ‘solidarity measures’. This risk cannot be prevented by recourse to adjudication, because no compulsory procedure for the settlement of disputes arising from the exercise of countermeasures has been agreed upon; moreover, though proportionality is indeed a limit to arbitrariness, it does not give satisfactory answers from a governance perspective.

There are two potential strategies for establishing some sort of ‘checks and balances’ and reaching a more equitable result. The first alternative could be that the more the self-contained regimes develop a normative awareness of regime-external community interests, and process the relevant issues through their own normative lenses and dispute settlement procedures (for example article XX and XXI GATT, DSU), the less it will be necessary for countermeasures to ‘pierce the veil’ of the regime from the outside and threaten its autonomy. It is arguable that the raison d'être of an expansive interpretation of countermeasures as solidarity measures would exist, as long as trade regimes behave as self-absorbed players, and devote only rudimentary attention to their normative environments, particularly to community interests. In the process of ‘socialization of regimes’, a tension between the evaluations by States and by regimes on the necessity of protecting external collective interests can be expected to arise, but comity considerations among the organs and actors involved may help adjust the differences and minimize incompatibilities over time.

A second built-in structural constraint could be the recognition of a link between countermeasures and UN Security Council assessments and evaluations. It is appropriate to recognize a ‘steering function’ to Chapter VI and VII determinations concerning the existence of a threat to the peace, or a potential threat to the peace, as long as the Council has imposed limited sanctions, or not at all. A determination of that kind enhances the legitimacy of solidarity measures, which would then be based on the authoritative and collective evaluation of the risk to community interests. As the resolutions usually construe the threat to the peace as violation of fundamental interests recognized by international law, the association between the centralized and the decentralized response with regard to wrongful acts becomes visible.

In a few instances one may strongly disagree with the standpoints of the author. Her appraisal that the 1973 Arab oil embargo was a case of legitimate countermeasures (pp 122–126) is in my view not well-founded, because she did not sufficiently explore the complex international law context of the situation in the Middle East, including the legality of the Yom Kippur War, and the obligations under UN Security Council Resolution 242/1967.Footnote ¹ Her argument that the Kadi ruling of the ECJ would imply a right of the EU Member States to exercise countermeasures in the form of violation of UN Security Council resolutions is also stretched too far (p 200). Nonetheless, the book is well-written, contains a wealth of information, and promotes the debate on this critical topic of international law.

Katselli Proukaki deserves credit for vigorously challenging the ILC approach with good arguments. Her scholarly work contributes greatly to the debate on solidarity measures as one of the still open issues of the law of State responsibility.