IN the second week of September, Houthi forces completed their seizure of Yemen’s Red Sea coastline, capturing Mocha and the island of Mayyun and placing themselves astride Bab al-Mandeb, the Strait carrying roughly twelve percent of global trade and eleven percent of the world’s seaborne oil. This followed seven months in which the Strait of Hormuz, carrying a quarter of the world’s maritime oil trade and a fifth of its LNG, passed through closure, ceasefire, reopening and renewed disruption after war broke out between Iran, Israel and the United States in February.
Daily transits through Hormuz, which averaged well over a hundred vessels before the crisis, fell at points to single digits. Together, these episodes expose the fragility of the global trading system and raise a question squarely within international law: who has the right to open, close, tax or control passage through the world’s most consequential waterways. The straits that matter most for global trade form a rough hierarchy. Hormuz, between Iran and Oman, remains the single most important energy chokepoint, moving some twenty million barrels of oil daily in ordinary times. Malacca, busier by vessel count with over a hundred thousand transits a year, carries roughly a quarter of global seaborne trade and twenty million barrels of oil daily, vital to China, Japan and South Korea. Bab al-Mandeb, the hinge of the Asia-Europe trade route via Suez, forces vessels around the Cape of Good Hope when closed, adding roughly two weeks and millions of dollars per voyage. The Bosphorus, Dardanelles and Gibraltar complete the list of waterways whose closure would be felt in every major economy within days.
None of these straits are canals and the distinction matters legally. Canals such as Suez and Panama are artificial works maintained by a controlling authority, which is why Egypt may lawfully toll under the 1888 Constantinople Convention and Panama under its own treaty. Straits, by contrast, are natural formations and the law governing them is navigational, not proprietary. The foundational precedent is the International Court of Justice’s 1949 Corfu Channel judgment, which held that states bordering a strait used for international navigation between two parts of the high seas cannot prohibit passage in peacetime, even by warships, absent a recognized legal basis, a ruling long since settled as customary international law. The 1982 UN Convention on the Law of the Sea then codified this principle through the regime of transit passage under Part III, Articles 34 to 45, applying to straits used for international navigation between one part of the high seas or exclusive economic zone and another. Transit passage is a stronger right than mere innocent passage: it cannot be suspended by the bordering state, even temporarily and Article 26 expressly forbids levying any charge on foreign ships merely for passing through, save for payment for specific services rendered. This is precisely why Hormuz, Malacca and Bab al-Mandeb cannot legally be tolled the way Suez is, whatever coastal states might wish.
The difficulty is enforcement against states and now non-state actors, unwilling to respect that regime. Iran is not a party to UNCLOS, though it accepts much of it as customary law while separately asserting a domestic-law right to restrict warship passage, a position most maritime states reject. The Houthi seizure of Yemen’s Red Sea coast raises a distinct problem: a non-state armed group, not a recognized sovereign, now exercises effective control over territory bordering an international strait. Under the law of state responsibility, Yemen’s internationally recognized government remains the duty-bearer for keeping the strait open, but has no practical capacity to do so, while attacks on shipping by an entity outside the formal treaty framework fall awkwardly between the law of the sea, the law of armed conflict and counter-piracy and counter-terrorism regimes, none of which was designed for a quasi-state actor holding a chokepoint. Naval coalitions escorting convoys through Hormuz and Bab al-Mandeb rest their legal justification on collective self-defence under Article 51 of the UN Charter and the customary right to protect freedom of navigation, but neither confers authority to compel a controlling power to reopen a strait it has chosen to close.
For Pakistan, this is not an abstract debate. Gwadar sits barely three hundred nautical miles from the mouth of Hormuz and Pakistan’s own oil and LNG imports transit the same strait now periodically closed by war. But the remedy does not begin with the weak; it begins with the strong. Customary international law survives only when the states most able to breach it choose instead to be bound by it and transit passage will constrain Iran or an armed group astride Bab al-Mandeb, only once the world’s leading maritime powers demonstrate, consistently rather than selectively, that the same rule binds them. That means Washington, which invokes freedom of navigation routinely, finally acceding to UNCLOS instead of standing outside the treaty it asks others to honour. It means the Security Council mandating a genuine multinational escort mission under Chapter VII in place of ad hoc coalitions that read as interest-driven. And it means referring disputed closures to the ICJ or the International Tribunal for the Law of the Sea rather than settling them by naval deployment alone. Only when the powerful bind themselves first can they credibly expect reciprocity from the weak, state or otherwise. Pakistan, as a dependent littoral state, should press precisely this sequencing at the IMO and the UN General Assembly: law before enforcement and great-power example before great-power demand.
—The writer is an international law expert and an internationally accredited arbitrator and mediator.
