In June 2025, 175 state actors renewed their commitments to the protection and resilience-building of marine ecosystems at the UN Ocean Conference (UNOC3), moving forward with an ambition “to transform ambition into action”. Yet, by late 2025, the world’s attention was drawn to entirely new problems in maritime diplomacy.
With the US war launched against Iran, the news has massively underlined the stakes regarding the Hormuz blockade, and the power (and fragilities) regarding the rule of maritime spaces. A hot topic that offers an opportunity for a quick dive into history and this new chapter of maritime diplomacy.
Long a catalyst for humanity’s fears and hopes, the seas and oceans continue to play a crucial role economically, politically, and culturally. As both a frontier by nature and a space for connection and transit, how can we make sense of this dichotomy in light of current events?
International Law: the complex case of maritime rule
Seas and maritime areas always hold a special place in international law. The divide in the debate, whether this space should stay ‘res communis’ (common good) or be ordered by the sovereignty of the land nearby, has fluctuated. This fluctuation depends on the role assigned or projected by this space of influence, both crucial in the conduct of alliances and trade but also in conquest and warfare.
In the globalization age, with the advent of means of mass surveillance and growing securitization of some borders (e.g. FRONTEX in Europe), but also the apprehension of softer – ‘phantom borders’, the bordering work becomes complexified and expands importantly. Playing on the ambiguity of both the ‘maritime security’ and ‘hybrid threats’, in a world where some borders tend to become ‘softer’ and more invisible, current geopolitics seems to be imposing an ever-stricter grid over marine areas. Whether this is to organize their protection, in the name of national security, or to exploit their resources.
Nonetheless, securitizing those spaces is a growing concern for both state actors and the companies whose products and cargo transit along those commercial routes.
The UNCLOS (1982), the United Nations Convention on the Law of the Sea, is one of the most ratified treaties in international law. It establishes a specific division of the sea and recognizes the sovereignty of states over their territorial seas and Exclusive Economic Zones (EEZs).
The neutral status of the high seas with regard to international law makes it a space prone to aggressive manifestation of power, avoiding the risk of retaliation or at least legal prosecution. This dynamic has been described as “low risk-high gain effort short of war”. But what about places like the Strait of Hormuz? As a strategic chokepoint in the flow of resources, it seems to be stirring up trouble due to its complex legal status and imperialist ambitions.
Hormuz Blockade
On 28 February 2026, Iran officially initiated a series of attacks on the Hormuz Strait. At its narrowest portion, the Strait (only about 33km wide) constitutes a key pathway for oil resources from Iran and other Gulf States like Kuwait or the United Arab Emirates to reach global markets. This creates a gray area in international law, particularly where the strait narrows, and ships must venture through the territorial waters of sovereign states.
Mines, drones, and missiles were deployed, effectively discouraging vessels from entering this sensitive pathway. This is part of the ongoing conflict, where both sides attack their opponent’s key energy infrastructure (such as the U.S. and Israeli strikes on Iranian oil depots)
Deterrence-wise, the Hormuz Strait and its blockade might be Iran’s most efficient asset against the U.S military assault. But it is also a global geopolitical time bomb. It is considered that about 20% of the world’s liquified natural gas (LNG) and oil transits through this path. Blockades have been enforced before, especially in the XXth century. However, the interconnectedness of global supply chains today makes the repercussions greater and more widespread than ever, especially in regions such as Asia.
UNCLOS Part III stipulates that, due to their overall strategic importance, the straits cannot be blocked. This armed blockade, therefore, runs counter to international law, prompting a variety of government responses to the disruption in the supply chain.
“We have taken the initiative to build a coalition in order to (…) secured in these sea lanes that are essential to the global economy”, declared French President Emmanuel Macron. This follows the deployment of France’s flagship aircraft carrier to the Mediterranean in March, in response to escalating tensions in the Middle East. France, as well as five other countries (Germany, Italy, Japan, the Netherlands, and the United Kingdom), are discussing the preparation of an intervention to open the Strait of Hormuz again. However, the specifics (timeline, means…) are yet to be decided.
The hybrid nature of the Strait of Hormuz is multifaceted: it stems from the maritime environment, which is difficult to secure, but also from its role as a key hub in the international transit network. Any response must take into account the wide range of issues and stakeholders affected by the precarious situation. As a result, while current events offer no clear path to a resolution, they highlight the difficulty of governing areas where commercial interests, state sovereignty, and open armed conflict intersect. This is particularly true in a globalized world that is still learning to address the challenges of contemporary polycrisis.
By Chloé Pierre
April 2, 2026
