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Two rocks surrounded by coral, with a total land size of less than 10 square meters (approximately 108 square feet) at high tide, are the entire basis on which Japan claims a 150,000-square-mile exclusive economic zone, an area nearly the size of Japan itself. The uninhabited feature, located more than 1,000 miles south of Tokyo, is called Okinotori.
In late July, Japan protested Sino-Russian live-fire drills held within the exclusive economic zone it claims around Okinotori. Tokyo cited the safety risks the drills posed to nearby vessels, but its broader objection was to Beijing’s claim that Okinotori is merely a rock entitled to no exclusive economic zone or continental shelf, as opposed to the island Japan claims it is.
While looking like a narrow dispute over the legal status of a tiny offshore feature, this episode is better understood as a point where East Asia’s legal and strategic contests intersect. Legally, this quarrel is a miniature of the region’s ongoing contest over maritime order: the 2016 arbitration ruling that China vehemently rejects is, ironically, what most undermines Japan’s claim that Okinotori is an island, and Tokyo, Beijing, and Washington each invoke the law of the sea where it suits them.
Strategically, China now confronts a simultaneity of tensions across the East China Sea, South China Sea, and the Taiwan Strait, heightened by deepening Japanese-Philippine coordination and an emerging alignment between Tokyo, Manila, and Taipei. Beijing’s response to this landscape has settled into an increasingly discernible pattern, with Okinotori being one of its nodes. At each point of contention, China pairs legal instruments with expanded physical presence: it delegitimizes its rival’s position, dresses its own in legality, and backs its position with intensified drills and patrols tailored to boost deterrence in each theater.
The legal status of Okinotori is at the core of the recent quarrel, but this issue is neither new nor loud: it has smoldered quietly for two decades. Japan insists that Okinotori — or, its preferred name, Okinotorishima (shima means “island”) — is an island. Under the United Nations Convention on Law of the Sea Article 121, a naturally formed feature that stays above water at high tide and can sustain human habitation or economic life of its own qualifies as an island entitled to a 200-nautical-mile exclusive economic zone and a continental shelf. On that basis, Japan claims an exclusive economic zone around Okinotori and, in its 2008 submission to the Commission on the Limits of the Continental Shelf, a continental shelf.
China, South Korea, and Taiwan all reject Okinotori’s status as an island. Beijing first objected in 2004, and since 2009, China and South Korea have each filed notes verbales with the Commission on the Limits of the Continental Shelf in response to Japan’s submission, contending that the feature is a “rock” incapable of sustaining human habitation or economic life of its own and therefore generating no exclusive economic zone or continental shelf. Because the Commission has no mandate to decide whether Okinotori is an island or a rock, this question has remained unresolved. Rather than endorse a continental shelf premised on the feature, the Commission’s 2012 recommendation deferred any decision on the portion of Japan’s submission based on Okinotori until the objections in China’s and South Korea’s notes are resolved.
Taiwan, though not a party to the U.N. Convention on Law of the Sea, likewise objects to Japan’s position. Its dispute with Tokyo has arguably been the most prominent of the three, centering on fishing rights within Japan’s claimed exclusive economic zone. In spring 2016, after the Japanese coast guard seized a Taiwanese fishing vessel near Okinotori, the Ma Ying-jeou (Kuomintang, or Nationalist Party) government protested Japan’s claim and dispatched coast guard vessels to protect Taiwanese fishing operations, straining ties with Tokyo. Since the Democratic Progressive Party took power later that year, Taipei has kept a lower profile on Okinotori but has not changed its official position that “the rights to the waters near Okinotori will remain in dispute.”
One point needs emphasis: None of the three neighbors challenges Japan’s sovereignty over Okinotori. Each has its own sovereignty disputes with Japan in the East China Sea or the Sea of Japan, but Okinotori is not among them. What is contested is its legal status and the maritime zones that status can generate.
The 2016 South China Sea arbitration ruling, which found that many of the Spratly features China claimed as islands are merely rocks under the law of the sea, directly undermines Japan’s own claim that Okinotori is an island. Although Japan immediately endorsed the ruling, it has been careful to frame it as binding only between China and the Philippines, applicable to the specific disputes the tribunal actually decided on but not to Okinotori.
Japan’s case is weak and legally difficult to sustain because the ruling’s test is general. Specifically, the ruling states: “Does the feature in its natural form have the capability of sustaining human habitation or an economic life? If not, it is a rock.” Okinotori cannot pass this test by any measure. By 2016, Japan had spent over $600 million protecting Okinotori from erosion and building an observatory to monitor passing ships. But the feature, in its natural form, has so far not sustained human habitation or economic activity of its own.
This point is not new. As Jerome Cohen and Peter Dutton, both leading law-of-the-sea scholars, noted shortly before the arbitration ruling,
the idea that Okinotori is entitled to control the economic resources of a sea covering roughly 150,000 square statute miles … has always been preposterous. No matter how generously the Philippine arbitration tribunal might interpret the terms of UNCLOS [the U.N. Convention on the Law of the Sea] Article 121.3 in the context of the South China Sea, it will not justify Japan’s claim.
Notably, they applied the same yardstick to both Beijing and Tokyo, calling Japan’s Okinotori claim and China’s South China Sea claims equally “absurd” and “unpersuasive” attempts to “capture more water space than either is entitled to.”
This weak legal foundation may explain a glaring omission: Japan protested the Sino-Russian drills without calling them unlawful. For one thing, the United States and its allies widely hold that foreign military operations in other states’ exclusive economic zones are lawful uses of the sea. More importantly, any objection on exclusive economic zone grounds presumes Okinotori generates such a zone in the first place, a premise Japan cannot persuasively defend. To accuse China of violating Japan’s exclusive economic zone would only have precipitated lawfare with Beijing surrounding whether that zone legitimately exists. Beijing, recognizing no such zone around Okinotori, exploited exactly the Japanese weak position and insisted that the exercises were conducted on the “high seas” and “fully consistent with international law.”
On the surface, the Sino-Russian exercises appear to be a direct response to Japan’s part in a joint statement marking the 10th anniversary of the 2016 arbitration ruling. In its reply, the Chinese foreign ministry asked rhetorically, without naming Japan:
If the “award” were to be taken as a standard, many countries’ islands and reefs would be denied the basis for claiming maritime rights and interests … [H]ave those countries supporting the “award” voluntarily waived the maritime rights and interests deriving from their relevant islands and reefs?
More pointedly still, after Japanese foreign minister Motegi Toshimitsu issued a standalone statement on the anniversary, China summoned Japanese diplomats and warned it would “respond firmly and forcefully to Japan’s provocations.”
But China’s show of force was more than a pushback against Japan’s anniversary statement. It came as a hardened response to Japan’s deepening involvement in the South China Sea and its tightening security partnership with the Philippines. This partnership took shape in the early 2010s, as tensions between China and its two rival claimants rose in both seas at the same time: in the East China Sea, the 2010 fishing trawler collision, the 2012 Diaoyu/Senkaku nationalization crisis, and China’s 2013 declaration of an air defense identification zone; in the South China Sea, the 2012 Scarborough Shoal standoff and, from 2014, China’s blocking of Philippine resupply to Second Thomas Shoal.
Against this backdrop, Tokyo steadily expanded maritime security cooperation with Manila, beginning with the strategic use of its Official Development Assistance to finance maritime capacity-building programs — including the transfer of 10 coast guard patrol ships for the Philippines — and accelerating after 2022 with the creation of the Official Security Assistance dedicated to strengthening partners’ capabilities to “prevent unilateral attempts to change the status quo by force.” The 2025 Reciprocal Access Agreement and the 2026 Acquisition and Cross-Servicing Agreement bound the two even closer.
Watching these developments warily, Chinese analysts warned that in building a “maritime surveillance system targeting China and the capacity to intervene in the South China Sea disputes,” Japan and the Philippines “underestimated China’s resolve to defend its territorial sovereignty and maritime rights and interests,” and that the partnership may further deepen as U.S. commitments to allies look less reliable under the second Trump administration.
The exercises were likely also intended as a warning to Tokyo over a newer issue: its maritime boundary delimitation talks with Manila — launched in May 2026 and covering waters east of Taiwan — which Beijing denounces as encroaching on Chinese maritime rights. Taipei’s response was deliberately calm. The Lai Ching-te (Democratic Progressive Party) government reaffirmed Taiwan’s “sovereign rights under international law and the law of the sea,” but dismissed any concern that the talks would harm Taiwan, adding that Beijing “has no right to comment on Taiwan’s policies … much less speak on behalf of Taiwan.” However, excluded from talks over waters overlapping its own claims and choosing not to take actions to press those claims itself, Taipei left a vacuum into which Beijing conveniently stepped, invoking its One China principle to assert the rights on Taiwan’s behalf and sending its coast guard vessels to patrol the area east of Taiwan.
Viewed in East Asia’s broader strategic context, the Sino-Japanese quarrel over Okinotori and the Sino-Russian joint exercises there look less like an isolated episode than one node in an increasingly coherent Chinese response to simultaneous pressure across the East China Sea, the South China Sea, and the Taiwan Strait.
In the East China Sea, tensions have been escalating since Prime Minister Sanae Takaichi’s 2025 remarks that a Taiwan emergency could threaten Japan’s survival. The flare-up was foreshadowed as early as 2021 when Japanese political leaders began explicitly articulating Taiwan’s importance to Japan’s security, and again in 2022 when China’s military response to Nancy Pelosi’s visit landed five ballistic missiles in Japan’s exclusive economic zone. In the South China Sea, frontline confrontations and clashes with the Philippines have intensified since 2023. And across the Taiwan Strait, tensions have increased steadily since the 2024 inauguration of Lai Ching-te, who has taken a tougher line toward Beijing’s pressure campaign than his predecessor, Tsai Ing-wen, and whom Beijing regards as a committed pro-independence figure.
Coincident tensions on China’s maritime periphery are not new. What is new is that Beijing’s rival claimants are now actively connecting all three fronts, turning coincidence into a looming geostrategic threat. Since 2025, the Philippines and Japan have floated a “one-theater” concept that treats the East and South China Seas as a single operational space. And the leaders of both Japan and the Philippines have suggested in recent months that their countries would likely be drawn into any fight over Taiwan — remarks that alarmed Beijing.
This is precisely the security landscape China’s strategists have long cautioned about — a “chain reaction” or “three-sea linkage” in which rival claimants coordinate with one another and with the United States to ratchet up pressure or open conflict on multiple fronts while Beijing needs to concentrate on Taiwan. Chinese strategists have an answer to this challenge, albeit not a comfortable one. Canonical military writings, including the various editions of Science of Military Strategy from China’s Academy of Military Science and National Defense University, hold that while China should employ every political, economic, and diplomatic means to prevent these fronts from igniting together, it must be prepared to fight on those terms if prevention fails: concentrating on the primary strategic direction (understood to mean Taiwan) while holding the line in secondary ones (here, the two seas, among others).
These writings suggest a China gearing up for a multifront predicament, and that preparation now appears to follow an increasingly discernible pattern. At each point of contention, China pairs legal instruments with expanded physical presence: lawfare aiming to delegitimize its rival’s position and strengthen China’s own, alongside intensified drills and patrols to signal resolve and boost deterrence tailored to each theater.
On the Japan front, Beijing coupled the exercises at Okinotori — part of a decade of growing Sino-Russian joint military activities near Japan — with the Article 121 test, the legal backbone of a ruling it rejects. On the Philippine front, China paired a fresh wave of joint military-coast guard drills with new nature-reserve administration rules at Scarborough Shoal. And east of Taiwan, Beijing launched coast guard patrols on top of its now-routine military pressure around the island, using the One China principle to justify acting on Taipei’s behalf.
Okinotori will not spark a war. But it is the latest manifestation of the region’s ongoing contest over maritime order, in which Japan, China, and the United States are each caught between legal consistency and strategic interests in their own approach toward the law of the sea and the 2016 arbitration ruling, and Taiwan between strategic alignment and its own claims. Okinotori is also a node in what appears to be an emerging pattern that Beijing has adopted in coping with the multifront predicament that its strategists long warned about.
For Japan, the tensions run deep. Tokyo has been among the arbitration ruling’s strongest proponents, persistently pressing its “final and legally binding” force on Beijing. However, the same logic, applied consistently, profoundly undermines Japan’s own claim that Okinotori is an island generating an exclusive economic zone and continental shelf. Thus, Tokyo cannot press the award harder without lending weight to the very test that fails its Okinotori claim.
For China, the mirror-image dilemma is that the ruling it has vehemently rejected is precisely what most effectively undermines Japan’s Okinotori claim. Beijing cannot invoke it to rebut Tokyo without acknowledging the legitimacy of a decision it has spent a decade denouncing. Therefore, Beijing maintains a tenuous position with a glaring legitimacy gap: opposing Japan’s claim to expansive zones around a tiny feature on the basis of the law of the sea, while claiming exactly such zones from small features of its own in the South China Sea. The legal awkwardness is compounded by a strategic quagmire: as China braces itself for the emerging multifront predicament it has long worried about, its coercive response — in both the legal and military dimensions — on each front has so far only given Tokyo, Manila, and Taipei new imperative to tighten their alignment.
For Taiwan, the dilemma is a strategic trade-off rather than legal inconsistency. Taipei shares Tokyo’s and Manila’s imperative to counter Chinese pressure, but the price of alignment may be acquiescing to a Japanese exclusive economic zone around Okinotori and to a Japan-Philippines delimitation, reached without Taipei at the table, in waters it claims — in exchange for partnerships it badly needs.
The Lai government insists it can leverage Taiwan’s fisheries agreements with Japan and the Philippines to protect Taiwanese fishing rights, but how it would do so with no say in a settlement overlapping its own maritime zone is unclear, and whether Taipei could defend such a trade-off domestically is equally doubtful. Meanwhile, Beijing’s readiness to “speak for” Taiwan turns Taipei’s silence and inaction into a fresh pretext for a sustained Chinese coast guard presence in waters east of the island — perhaps establishing a new normal that could hollow out Taiwan’s fisheries agreements even if Tokyo and Manila are willing to accommodate Taipei’s interests.
For the United States, Okinotori embodies a trade-off between legal consistency and alliance value. Washington has long resisted China’s expansive maritime claims from tiny South China Sea features — a position that serves U.S. navigational interests — and pressed the 2016 award on Beijing. But it has stayed conspicuously silent on Okinotori, whose entitlement rests on the same reasoning. A consistent application of the legal logic would require the United States to treat Okinotori as a rock and push Japan to do the same. Some may defend U.S. selectivity as a deliberate strategic choice: Washington tolerates Japan’s weak Okinotori claim because the alliance is worth more than legal consistency, and ambiguity preserves flexibility and alliance solidarity that consistency could undermine. Moreover, legal consistency might even force the United States to reconsider its own claims to expansive zones around remote uninhabited islets such as Howland and Baker Islands.
Deliberate ambiguity, however, can play into Beijing’s hand, not to Washington’s or its allies’, as illustrated in the July Sino-Russian military exercises. China conducted drills within Japan’s claimed exclusive economic zone while dressing its operations with legality, and Japan could not even mount a legal challenge without exposing its own weak claim. More broadly, every episode of U.S. selective silence may lend further credence to Beijing’s narrative that the rules-based order that Washington (and Tokyo) upholds means rules for others, not for the United States or its friends.
Nor would consistency cost what its skeptics worry about. It does not necessarily require the United States to openly declare Okinotori as a rock. Rather, Washington could take the position that the arbitration ruling’s interpretation of Article 121 is universally applicable — to features claimed by friend and foe alike — while taking no position on any specific feature. This approach is logically akin to the neutrality that the United States has long maintained on sovereignty disputes between Japan and its East Asian neighbors. Washington could quietly push Tokyo to keep its claim politically and operationally dormant, protesting Chinese military activities on safety grounds without calling them unlawful — an approach Japan’s response to the July drills already follows.
The cost of consistency is manageable friction with an ally, for whom Okinotori carries symbolic value and $600 million in sunk investment. The benefit is denying Beijing its favorite rhetorical line: casting the alliance’s invocation of the law of the sea as selective and self-serving to justify China’s own double standard between Okinotori and the South China Sea. By insisting on consistency, Washington would also be effectively competing for the opinion of third-party audiences in Asia and beyond who will increasingly shape the maritime order — and who have been watching to see whether the rules bind everyone, or only the other side.
Shuxian Luo is an assistant professor at the University of Hawai’i and author of Simmering Seas: Escalation and De-escalation in China’s Maritime Disputes (Oxford, forthcoming in October 2026). Her work has appeared or is forthcoming in Texas National Security Review, Asian Security, The Pacific Review, Journal of Contemporary China, Contemporary Southeast Asia, Foreign Affairs, Military Review, and The Diplomat, among others.
