The United States and China's Nine-Dash Claim
Early last month, the U.S. State Department released the latest in its Limits in the Seas series. These surveys examine the maritime claims of nations around the world and analyze whether they are consistent with international law.
Normally, these reports constitute fascinating reading for a small community of maritime law enthusiasts, but they tend to be fairly bloodless otherwise. Not so with the latest, though: No.
Published by The Lawfare Institute
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Early last month, the U.S. State Department released the latest in its Limits in the Seas series. These surveys examine the maritime claims of nations around the world and analyze whether they are consistent with international law.
Normally, these reports constitute fascinating reading for a small community of maritime law enthusiasts, but they tend to be fairly bloodless otherwise. Not so with the latest, though: No. 143 brings China’s maritime claims in the South China Sea under sustained legal scrutiny and finds them wanting.
This report is valuable on its own terms as the most developed and detailed U.S. government position on China’s maritime claims in the South China Sea. After all, up until recently, the American government has been somewhat reticent to publicly announce its position on China’s maritime claims. But besides adding another round of criticism to the barrage that started last February with Assistant Secretary Russel and U.S. Chief of Naval Operations Admiral Greenert, the report may also have significant implications for the ongoing arbitration between the Philippines and China over the latter’s maritime claims in the South China Sea. In particular, the report demonstrates a possible method by which the tribunal can skirt one of the most challenging issues in the litigation—figuring out what, exactly, China’s claims actually are.
Accordingly, Lawfare summarizes the contents of the report below the fold.
I. China’s Nine-Dash Line
The report begins by describing China’s claims to parts of the South China Sea from both a historical and a geographic perspective. In recent years, China’s claims have largely been understood by reference to the infamous “nine-dash” line, which appeared on a map presented by China to the international community in 2009.
According to the 2009 map, the nine-dash line runs along Vietnam’s coast, crosses the South China Sea to the coast of Malaysia, and then snakes its way up along the Malaysian, Bruneian, and Philippine coasts before finishing east of Taiwan. As the report notes, the nine-dash line darts extremely close to the coasts of neighboring states—in fact, the dashes are generally closer to those coasts than they are to any islands within the South China Sea.
When it submitted the map, Beijing said simply that “China has indisputable sovereignty over the islands in the South China Sea and the adjacent waters, and enjoys sovereign rights and jurisdiction over the relevant waters as well as the seabed and subsoil thereof (see attached map).”
II. Basis of Analysis
Next, the report turns to the relevant maritime law as reflected in the U.N. Convention on the Law of the Sea (UNCLOS). In most cases, the rules are relatively simple once a state knows the land feature from which it is measuring a maritime zone. Coastal states are entitled to a territorial sea stretching 12 nautical miles from their coastal baselines. They also get more limited sovereign rights for certain purposes within their exclusive economic zones (EEZs)—which extend up to 200 nautical miles from the coastal baselines—and over their continental shelf, which is the seabed and subsoil of the submarine areas that extend beyond the territorial sea to the outer edge of the continental margin or up to 200 nautical miles.
But the rules get a little more complicated with respect to islands. Technically speaking, an island is “a naturally formed area of land, surrounded by water, which is above water at high tide.” Accordingly, if a maritime feature is not above water at high-tide—in other words, if it is a “low-tide elevation” or a submerged feature—then it is generally not entitled to any maritime zone. Instead, these features are considered part of the seabed and subsoil, so they are “subject to the regime of the maritime zone in which they are found.”
But if the maritime feature does poke its head above water at high tide, then it counts as an island. For the most part, islands get the same maritime zones as other types of land territory. However, there is an exception: if an island “cannot sustain human habitation or economic life of [its] own,” then it is characterized as a “rock.” Rocks do not generate entitlements to either EEZs or continental shelves; in other words, they are limited to a 12 nautical mile territorial sea.
In short, it matters tremendously for the purpose of drawing maritime zones whether a feature is a habitable island, a rock, or a low-tide elevation/submerged feature. (Parenthetically, these distinctions are at the heart of Manila’s pending arbitration case against China—the Philippines claims that regardless of who has sovereignty over the maritime features, many of these features are not habitable islands, and thus they do not generate entitlements to the wide-ranging sort of maritime zones that China seems to assume they do.)
Finally, this section of the report touches on the international law relating to “historic” bays and titles. The United States takes the position that in order to establish the existence of this type of maritime entitlement, a claimant must demonstrate “(1) open, notorious, and effective exercise of authority over the body of water in question; (2) continuous exercise of that authority; and (3) acquiescence by foreign States in the exercise of that authority.” Perhaps most importantly, historic bays and titles are “strictly limited geographically and substantively” – they “apply only with respect to bays and similar near-shore coastal configurations, not in areas of EEZ, continental shelf, or high seas.”
III. Analysis
The report opens its analysis by distinguishing between China’s claims to territory in the South China Sea—in other words, claims of sovereignty over habitable islands and rocks—and its claims to the Sea’s waters. The report disclaims any interest in analyzing China’s territorial claims, and instead, it focuses solely on China’s maritime claims.
At this point, the U.S. government runs into a problem. Beijing has never clarified the nature of its maritime claims within the nine-dash line; indeed, it has sent a variety of contradictory messages, and its 2009 statement on the matter is maddeningly unhelpful and seemingly designed to obscure rather than clarify. To evade this legal fog, though, the study cleverly analyzes three possible interpretations of China’s nine-dash line claim, and whether any of those interpretations are consistent with the international law of the sea. We’ll address each interpretation in turn.
First, the nine-dash line may simply “indicate[] only the islands over which China claims sovereignty.” If so, then the line does not raise any interesting questions under maritime law. Instead, China would presumably be limited in its maritime claims to any zones to which it is entitled under UNCLOS rather than all the waters enclosed within the nine-dash line.
Second, the nine-dash line could alternatively be interpreted as indicating a “national boundary between China and neighboring States.” If so, then the line is inconsistent with international law. China cannot unilaterally decide where its borders end because neighboring states must delimit boundaries “by agreement.” In addition, the line “lack[s] other important hallmarks of a maritime boundary, such as a published list of geographic coordinates and a continuous, unbroken line that separates the maritime space of two countries.” And even if the line is taken as a unilateral position on what the boundary should be, Beijing has failed to explain why the boundary should be drawn so close to other States’ coasts and so far from even the South China Sea islands claimed by China. Plus, Beijing has not explained “the related question of what kind of rights or jurisdiction China is asserting for itself within the line,” which becomes a serious issue because in several cases, the line’s dashes are located beyond even the 200 nautical mile limit of EEZs from Chinese-claimed land features.
Third and finally, the nine-dash line could be read as marking out the limits of a “historic” claim. As the report notes, a “historic claim might be one of sovereignty over the maritime space (‘historic waters’ or ‘historic title’) or, alternatively, some lesser set of rights (‘historic rights’) to the maritime space.”
As a threshold matter, the report argues that China has not even made a “cognizable claim to either ‘historic waters’ or ‘historic rights’ to the waters of the South China Sea within the dashed line.” International law requires “international notoriety” in asserting a historic claim to put other countries on notice of the possible existence of such a claim. Problematically for Beijing, “there appears to be no Chinese law, declaration, proclamation, or other official statement describing and putting the international community on notice of a historic claim to the waters within the dashed line.” Worse, China’s claims “lack the precision, clarity, and consistency that could convey the nature and scope of a maritime claim.” Indeed, Beijing has never released the geographic coordinates of any of the nine dashes, and the location (and size) of the dashes seems to vary from map to map. These inconsistencies can be substantial: for example, one dash appears 45 nautical miles closer to Vietnam’s coast on the 2009 map than it does on a 1947 map.
But even if Beijing had made a cognizable claim, it would violate international law. In the first instance, “the LOS Convention limits the relevance of historic claims to bays and territorial sea delimitation.” In contrast, the nine-dash line encompasses open waters far from any nearby islands. The claim also fails every element of the three-part legal test for historic waters described earlier: the claim was not made openly or notoriously (indeed, it is still unclear!); China has not exercised effective and continuous authority in those waters (for instance, other states have used the waters of the South China Sea); and no state has recognized or acquiesced to any exercise of Chinese authority in those waters (and “[a]ny alleged tacit acquiescence by States can be refuted by the lack of meaningful notoriety of any historic claim by China”).
In sum, the report concludes that “unless China clarifies that the dashed-line claim reflects only a claim to islands within that line and any maritime zones that are generated from those land features in accordance with the international law of the sea, as reflected in the LOS Convention, its dashed-line claim does not accord with the international law of the sea.”
Sean A. Mirski practices a combination of foreign-relations, international, and appellate law at Arnold & Porter in Washington, DC. He is also a Visiting Scholar at the Hoover Institution. He clerked for Justice Samuel A. Alito, Jr., on the United States Supreme Court, and for then-Judge Brett M. Kavanaugh on the United States Court of Appeals for the D.C. Circuit. He also served as Special Counsel to the General Counsel of the U.S. Department of Defense. He is the author of We May Dominate the World: Ambition, Anxiety, and the Rise of the American Colossus, which Kirkus selected as one of the 100 Best Non-Fiction Books of 2023.