Conclusion

China has not given up maritime claims based on the U-shaped line and recent practice has demonstrated that China is attempting to further consolidate the claim based on the line; in particular by undertaking regular and intensified law enforcement patrols in the South China Sea within the line.
There is no denying that the U-shaped line carries some legal implications for the settlement of territorial and maritime disputes in the South China Sea. China’s submission of the U-shaped line map to the United Nations makes it clear that the line is connected to China’s claim over continental shelves in the South China Sea. It has been observed that the line is coincidental with the 200-meter isobath in the South China Sea.89 This was the general definition of the outer limit of the continental shelf provided for in the 1958 Convention on the Continental Shelf.90 One can argue that the line in the South China Sea was intended to define the continental shelves of the islands within the line. The line along the 200-meter isobath may have been influenced by the 1945 Truman Proclamation.91 The U-shaped line was officially proclaimed more than a half-century before the adoption of the LOS Convention and a decade before the adoption of the 1958 Geneva Convention. The historic rights derived from or area delineated by this line cannot be disregarded. Usually the regime of historic rights is favorable for states with a long history, but relatively unfavorable for the newly independent states founded after World War II. This concern was noted when the issue of historic waters was discussed in the UN International Law Commission in the 1950s. Garc´ıa-Amador contended that the concept of historic bays benefited only older countries having a long history and that there were many comparative newcomers to the international community—countries in Latin America, the Middle East
and the Far East—which could not claim such historic rights.92 In comparison with the claims by other countries bordering the South China Sea, China’s claim has the longest history. This fact can at least partially explain why other claimants to the islands in the South China Sea are opposed to China’s historic claims based on the U-shaped line. On the other hand, China faces a dilemma regarding the line as it is not yet ready to give a reasonable explanation of the line based on international law. Since there are no express legal provisions in the LOS Convention that can be used as a legal basis to support China’s U-shaped line, China is unable to use the LOS Convention to defend its unilateral line in the South China Sea. While the LOS Convention affirms that matters which are not regulated under it should continue to be governed by general international law including customary law, it seems that China faces a dilemma of having no sufficient
expertise in international law to explain the U-shaped line. Thus, China has remained silent when it has been asked or challenged by its neighboring countries for an explanation.93 After communicating the U-shaped line map to the United Nations, China has encountered increased pressure, particularly from the ASEAN countries, for an explanation of the line. Even Singapore, a nonclaimant state in Southeast Asia, has raised concerns about the ambiguous claim made by China in the South China Sea.
China has been trying to apply the LOS Convention to the South China Sea. China has enacted a number of laws in accordance with the LOS Convention, including the 1992 Law on the Territorial Sea and the Contiguous Zone94 and the 1998 Law on the EEZ and the Continental Shelf.95 China used straight baselines to define part of its territorial sea along the mainland coast as well as encircling the Paracel Islands.96 It is predicted that once the EEZ and continental shelf problems are settled for the South China Sea islands, the significance of the U-shaped line will be reduced. In the meantime, the line will be the legal and historical basis for China to defend its territorial and maritime claims in the South China Sea. China has to use the line as a countermeasure against the claims of other states to EEZs and continental shelves in the South China Sea. This has recently been demonstrated in the Chinese objection to the submissions by Vietnam and Vietnam-Malaysia to the CLCS.As for any dispute resulting from an explanation on the U-shaped line, China can rely on Article 298 of the LOS Convention, which permits states parties to exclude the compulsory procedures provided for in the Convention from applying to the disputes “involving historic bays or titles.” China has exercised this right through its declaration of exclusion in 2006.97 Like many states, China prefers bilateral negotiations to settle territorial and maritime disputes with its neighbors. Through negotiations, China can use its persuasive power to entice its counterparts to reach an agreement. This approach had had some success as evidenced by the conclusion of the Tripartite Agreement on Seismic
Activities in the South China Sea among three state-owned oil companies from China, the Philippines, and Vietnam in March 2005.98 Though the agreement expired in 2008 with no substantial progress, it is perceived that China will continue in its efforts to reach similar agreements for cooperation in the South China Sea. The U-shaped line is also a dilemma for the ASEAN claimant countries. Given the ambiguity of the basis of the line, except for using words such as “legally groundless” or “null and void,” other claimants cannot rely on norms and rules of international law to rebut China’s U-shaped line. At least three important research questions arise from the U-shaped line. First, is the LOS Convention the only international law to be relied on to explain the U-shaped line? Second, is there support for the U-shaped line in general international law including customary law? Third, do maritime rights that are set out in the LOS Convention override rights that existed prior to the adoption of the LOS Convention?