Two Weeks in Review: 23 February—6 March 2026

Here we go again? Last weekend saw yet another shock to the system, as the US and Israel launched an armed attack on Iran: the last week on the blog has seen some initial reactions. These are joined by analyses of the hard-fought (and already faltering?) EU-Mercosur trade agreement, regional shifts in dispute settlement under UNCLOS, an apparently new move to managing investment through trade, and a continuation of the discussion on climate obligations in domestic courts. Not to mention a new podcast episode and posts in our joint symposium with Just Security on the ICRC’s Updated Commentary on the Fourth Geneva Convention.  

US-Israel attack on Iran

Marko Milanovic gives two short assessments on the US-Israel military strike against Iran. In a first post, he argues that the strikes constitute a clear violation of the prohibition on the use of force under Article 2(4) of the UN Charter. He rejects claims of self-defence under Article 51, concluding that there was no ongoing or imminent armed attack that could justify either individual or collective self-defence, even under broad theories of anticipatory action. Preventive force based on speculative future threats cannot be reconciled with the Charter framework. In short, the strikes are plainly unlawful under international law, regardless of political context or consequences.

In a second post, he makes the case that while the US and Israel’s strikes on Iran are unlawful, the UK’s response—intercepting Iranian missiles and allowing limited use of its bases for defensive purposes—can be lawful under the doctrine of collective self-defence in Article 51 of the UN Charter. Marko contends that although Iran initially had a right to self-defence, its missile attacks on Gulf states not directly involved in the US-Israeli attack exceed necessity and proportionality, thereby constituting armed attacks that justify assistance from states like the UK at the request of those affected countries. The UK’s actions are therefore framed as strictly defensive and limited to repelling ongoing attacks, provided they do not facilitate broader strikes unrelated to collective self-defence. The key legal safeguard is ensuring that UK facilities are used solely for proportionate defensive operations.

Trade: binding investment, bypassing democracy?

Victor Crochet and Tessa Sophie Hoffmann trace the renewed use of tariffs to influence where investment occurs in the global economy. While tariffs historically encouraged “tariff-jumping” investment, modern trade agreements increasingly link market access directly to explicit investment commitments, as illustrated by the Trade and Economic Partnership Agreement between India and the EFTA, and recent US trade deals. Because governments cannot legally compel private firms to invest abroad, such commitments are often politically rather than legally enforceable. They argue that the European Commission is developing a distinctive approach by tying tariff relief to binding investment commitments through trade-remedy instruments like price undertakings, effectively creating enforceable “state-to-business” obligations while remaining within the framework of the WTO system.

Alexandre Lejeune turns our attention to recent developments in EU-Mercosur trade. After more than 20 years of negotiations, the EU and Mercosur finally signed a major trade package in January 2026—but the European Parliament has postponed its approval vote and requested an opinion from the European Court of Justice, raising a question mark about provisional application. Alexandre argues that the Council of the European Union has already effectively authorized provisional application of the trade component, leaving the European Commission with little discretion once Mercosur states confirm their participation. The agreement may take effect temporarily without parliamentary approval, raising concerns about democratic accountability and the capacity of EU governments to bypass parliamentary scrutiny in trade policy.

Climate obligations in domestic courts

Picking up on a discussion of a few weeks ago, Flore Heinrich and Sophie Starrenburg pull focus on the Hague District Court’s judgment in Greenpeace v. Netherlands concerning the Dutch government’s climate obligations toward Bonaire, a Caribbean municipality of the Kingdom. Although the case is a landmark for addressing climate change’s impact on cultural heritage, they argue the court relied narrowly on Article 8 ECHR, missing the opportunity to draw on broader international human rights and cultural heritage frameworks that could have strengthened its reasoning. It also limited its remedy to requiring “effective measures” without addressing reparations, leaving unresolved questions about compensation and recognition for cultural losses.

Joint Symposium: ICRC updated commentary on Geneva IV

Our Joint Symposium with Just Security on the International Committee of the Red Cross’s updated commentary on the Fourth Geneva Convention continues with two more interventions.

The updated commentaries draw extensively on decades of State practice and raise important questions about the role of subsequent practice in treaty interpretation under Articles 31–32 of the Vienna Convention on the Law of Treaties. Abhimanyu George Jain and Ellen Policinski examine two examples to show how inconsistent State practice can have different interpretive effects. In the case of the grave breaches regime, despite uneven implementation, the practice does not undermine the mandatory nature of the obligations. By contrast, widespread non-use of the protecting powers system has led the Commentary to conclude that those provisions have become optional in practice, illustrating how subsequent practice must be assessed contextually rather than mechanically.

Jelena Pejic explains that internment—non-criminal detention based on security threats—is a central but only partly regulated feature of international humanitarian law (IHL), especially under the Fourth Geneva Convention. She highlights a legal gap during the invasion phase of international armed conflicts, when the Convention’s detailed procedural safeguards for civilian internees may not formally apply. A growing “functional” approach to occupation, endorsed by scholars and reflected in recent commentary and case law, supports applying key internment protections based on the degree of control exercised rather than a strict invasion/occupation distinction.

Ghana-Togo maritime delimitation

Andreas Giorgallis argues that Ghana’s decision to initiate Annex VII arbitration under UNCLOS reflects both the exhaustion of prolonged bilateral negotiations with Togo, and Ghana’s established preference for binding third-party dispute settlement. He situates the dispute within the Convention’s framework for maritime delimitation (Articles 74 and 83) and compulsory dispute resolution under Part XV, highlighting that arbitration is the default mechanism where States have not agreed otherwise. Both States’ legal and institutional frameworks support recourse to arbitration and the process may coexist with continued negotiations or provisional arrangements. The case is part of a broader regional shift toward structured, rule-based maritime boundary resolution, while its outcome will depend on good faith engagement by both parties.

The Podcast

In Episode 41 of the podcast, Andrew Lang (University of Edinburgh, UK) is joined by Michelle Ratton Sanchez Badin (FGV Sao Paulo School of Law, Brazil) and Nicolás M. Perrone (Universidad de Valparaiso, Chile). Starting from Mark Carney’s influential speech at the World Economic Forum, they reflect on how we should be thinking about rupture—and continuity—in relation to the contemporary international economic order. What is happening to international law, the purposes to which it is being put, its centrality as a technology of governing over distance, its status as a carrier for aspirations to multilateralism and universalism? Are we in fact living through a period of rupture or merely witnessing a hegemon’s loss of faith in its own international legal tools? Tune in for a particular focus on how Latin America is experiencing and reacting to this moment of crisis—or, perhaps, opportunity.

As ever, you can find events and anouncements here.