Yuan Feng* and Yongming Jin**
The world's oceans have become increasingly central to human affairs. As our reliance on them for trade, resources, and data transmission deepens, so too does the competition for maritime space and influence. As this competition intensifies, so does the imperative to govern the ocean commons in an effective, equitable, and sustainable manner. At the heart of this challenge is the dynamic relationship between maritime order – the de facto state of affairs at sea – and the rules of the sea that are designed to shape it. It is not a static relationship but rather an unceasing dialogue – one that has evolved from raw assertions of power into a complex system of rights, duties, and shared responsibilities.
This evolution began with a foundational clash of ideas. In the 17th century, the Dutch jurist Hugo Grotius, in his seminal work Mare liberum ('The free sea'), argued that the seas were the common property of all, too vast to be owned by any single nation.[i] This principle of the 'freedom of the seas' became a catalyst for global trade and interaction. However, this view was soon challenged by England's John Selden, whose treatise Mare clausum ('The closed sea') argued that coastal states could – and indeed should – exercise sovereignty over adjacent waters to protect their security and resources.[ii] This tension between the universal freedom of navigation and the sovereign interests of coastal states gave birth to the concept of the territorial sea. Initially, the territorial sea was defined by the pragmatic 'cannon-shot rule', limiting a coastal state's control to the range of its shore-based artillery. This compromise marked the first major step toward a rules-based maritime order.
For centuries, this fragile balance was maintained through custom and the power of dominant navies. However, the 20th century brought technological advances and a surge in resource claims that threatened to unravel this customary order. The mid-20th century saw a monumental shift from duelling customs to concerted codification. The international community, recognising the need for clarity and predictability, embarked on an ambitious project to codify the law of the sea. The 1958 Geneva Conventions were a significant first step,[iii] but the 1982 United Nations Convention on the Law of the Sea (UNCLOS) emerged as the widely heralded 'constitution for the oceans'.[iv] UNCLOS embodies a carefully balanced compromise that accommodates the interests of coastal states, flag states, and the international community at large. It delineates maritime zones – from the territorial sea and contiguous zone to the exclusive economic zone (EEZ) and the high seas. It also establishes governance frameworks for activities such as international navigation, fisheries management, marine scientific research, and environmental protection.
Yet, UNCLOS was never intended to remain static. Its drafters included mechanisms to address issues unforeseen at the time. The Convention's preamble affirms that matters not regulated by UNCLOS remain governed by general international law. Moreover, its dispute-resolution clauses allow tribunals to apply other compatible legal rules. This built-in flexibility has allowed the law of the sea regime to adapt to changing circumstances. The international community has built upon the UNCLOS foundation with key implementing agreements, such as the 1995 UN Fish Stocks Agreement,[v] and the 2023 'High Seas treaty'[vi] to protect biodiversity in areas beyond national jurisdiction. These agreements demonstrate a collective commitment to strengthening ocean governance in the face of new challenges like overfishing and biodiversity loss.
Today, the dialogue between maritime order and the rules of the sea is being tested by a shifting geopolitical landscape. The rise of new maritime powers, particularly from the Global South, presents new challenges and opportunities for the UNCLOS regime. China, for instance, ratified UNCLOS in 1996 and has since developed an extensive body of domestic maritime law reflecting UNCLOS's principles. Such integration is a testament to the Convention's global reach.
Yet, points of friction remain. Certain national laws and claims, especially on security considerations,[vii] and maritime entitlements,[viii] continue to generate debate within the international community. These issues are not merely technical; they raise deeper questions about the nature of maritime order. Contemporary controversies prompt us to ask whether the existing rules are adequate, and how they should be interpreted in light of evolving realities.
Amid these debates, concepts such as the Chinese notion of a 'maritime community with a shared future'[ix] invite deeper scholarly engagement. Such ideas prompt the international community to consider how emerging principles might be clarified and integrated into the existing legal framework to enhance maritime governance.[x] Engaging in such dialogue is essential to ensure that the rules of the sea remain relevant and robust.
Ultimately, maritime order and the rules of the sea are inextricably linked. A stable and predictable order is only possible through adherence to shared rules, and those rules must continue to evolve to meet the demands of a changing world. Honouring the legacy of visionaries like Bonaya Godana calls for a steadfast commitment to a rules-based maritime order. Only through collective efforts in scholarship, diplomacy, and practice can we ensure that the oceans remain open, secure, and sustainable for all.
* School of International Affairs and Public Administration, Ocean University of China, Qingdao 266100, China; Institute of Marine Development, Ocean University of China, Qingdao 266100, China; Centre for International Law, National University of Singapore, Singapore 259770, Singapore. These authors have contributed equally to this work and share first authorship.
** School of International Affairs and Public Administration, Ocean University of China, Qingdao 266100, China; Institute of Marine Development, Ocean University of China, Qingdao 266100, China. Corresponding author. E-mail address: This email address is being protected from spambots. You need JavaScript enabled to view it.. These authors have contributed equally to this work and share first authorship.
[i] Hugo Grotius, The free sea, trans. Richard Hakluyt, Liberty Fund, 2004.
[ii] John Selden, Mare clausum. Of the dominion, or ownership of the sea, translated by M Nedham, William Du Gard, 1652.
[iii] United Nations, Convention on the Territorial Sea and the Contiguous Zone, 29 April 1958, 516 UNTS 205; United Nations, Convention on the High Seas, 29 April 1958, 450 UNTS 11; United Nations, Convention on the Continental Shelf, 29 April 1958, 499 UNTS 311; United Nations, Convention on Fishing and Conservation of the Living Resources of the High Seas, 29 April 1958, 559 UNTS 285; United Nations, Optional Protocol of Signature concerning the Compulsory Settlement of Disputes, 29 April 1958, 450 UNTS 169.
[iv] United Nations, United Nations Convention on the Law of the Sea, 10 December 1982, 1833 UNTS 3.
[v] United Nations, Agreement for the Implementation of the Provisions of the United Nations Convention on the Law of the Sea of 10 December 1982 relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks, 4 August 1995, 2167 UNTS 3.
[vi] United Nations, Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction, 19 June 2023 (not yet in force).
[vii] Jing Geng, 'The legality of foreign military activities in the exclusive economic zone under UNCLOS' 28 Merkourios: Utrecht Journal of International and European Security Law (2012) 22-30.
[viii] Enrique A Manalo, 'Solidarity for SDGs and a Just, Equitable and Rules-Based Order', Statement of the Secretary for Foreign Affairs, Republic of the Philippines at the United Nations General Assembly 78th Session, 23 September 2023, 3.
[ix] Jin Yongming and Cui Ting, 'On the ''maritime community with a shared future" solving the predicaments of global ocean governance system in a tridimensional manner (in Chinese)' 10 Journal of Social Science (2023) 102-114; Weibin Zhang, Yen-Chiang Chang and Liangfu Zhang, 'An ocean community with a shared future: Conference report' 116 Marine Policy (2020) 103888; Qi Xu and Ziyue Tan, 'Building a maritime community with a shared future: Scholarly reflections on China's new ocean vision' 149 Marine Policy (2023) 105508.
[x] Wang Yi, 'Coexisting in harmony and working together to bring global ocean governance to a higher level', Remarks at the opening ceremony of the symposium on Global Maritime Cooperation and Ocean Governance 2024, Ministry of Foreign Affairs, Republic of China, 26 November 2024, <https://www.mfa.gov.cn/eng/wjbzhd/202411/t20241126_11533290.html> on 15 August 2025.
