China’s ambiguous claim to the South China Sea, approximately demarcated by a series of hash marks known as the “nine-dashed line,” faced objections from an expanding number of parties over the past two weeks. While a challenge from the United States came from an unsurprising source, actions by Indonesia and Vietnam were unexpected in their tone and timing.
On Dec. 5, the U.S. State Department released its analysis of the compatibility of China’s nine-dashed line with international law. The report attempted to set aside the issue of sovereignty and explore “several possible interpretations of the dashed-line claim and the extent to which those interpretations are consistent with the international law of the sea.” The analysis found that as a demarcation of claims to land features within the line and their conferred maritime territory, the least expansive interpretation, the claim is consistent with international law but reiterated that ultimate sovereignty is subject to resolution with the other claimants.
As a national boundary, the report went on, the line “would not have a proper legal basis under the law of the sea,” due to its unilateral nature and its inconsistent distance from land features that could confer maritime territory. Alternately, although many commentators have indicated China bases its claims on “historic” rights predating the U.N. Convention on the Law of the Sea (UNCLOS) of 1982, the report argued that the history China points to does not fit the narrow “category of historic claims recognized” in UNCLOS, under which historic rights may be conferred. Lastly, the report noted that because China has filed no formal claim supporting its nine-dashed line, the ambiguity over the exact nature and location of the line itself under international law undermines China’s argument that it possesses maritime rights to the circumscribed waters, concluding:
“For these reasons, 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.”