Inventor of China’s nine-dash line | Inquirer Opinion

Inventor of China’s nine-dash line

The root cause of the South China Sea dispute is China’s nine-dash line that appears in the 1947 map invented by the Kuomintang Party, which controlled the Chinese government at that time. The 1947 map is titled “Location Map of South Sea Islands,” clearly signifying a claim to islands and their territorial seas, and not a claim to the waters and resources within the nine-dash line beyond the territorial seas. The nine-dash line encloses about 85.7 percent of the South China Sea. At that time, international law recognized a territorial sea of only three nautical miles. Beyond the territorial sea were the high seas which belonged to all mankind.

When the communists won the civil war in China in 1949 and the Kuomintang nationalists fled to Taiwan, the Chinese Communist Party (CCP) inherited the nine-dash line claim. Originally, there were 11 dashes but, in early 1950s, the communist government of China dropped two dashes in the Gulf of Tonkin as a gesture of friendship to the communist government of North Vietnam. In 1992, China enacted its Law on the Territorial Sea and Contiguous Zone which adopted a 12-nautical mile territorial sea from the baselines along the coast of China’s continental land and island territories. In 1998, China enacted its Exclusive Economic Zone and Continental Shelf Act claiming a 200-nautical mile EEZ from the same baselines from which its territorial sea is measured. These maritime zones are generally in accordance with the 1982 United Nations Convention on the Law of the Sea (Unclos) to which China is a party.


This 1998 Act, however, states that the Act “shall not affect the historical rights” of China, a provision that runs counter to Unclos which extinguished all historic rights in the EEZ. Under Unclos, the adjacent coastal state has “exclusive” sovereign rights to exploit its EEZ. States that ratify Unclos, like China, are not allowed to make reservations or exceptions to its provisions unless expressly allowed under Unclos, which does not allow such reservations or exceptions to the exclusivity of the EEZ. China, nevertheless, claims all the waters and resources within the nine-dash line by “historical rights,” depriving five Asean states—the Philippines, Vietnam, Malaysia, Brunei, and Indonesia—huge areas of their respective EEZs.

Taiwan is in possession of Itu Aba, at 46 hectares the largest island in the Spratlys. In early 2016 Taiwan, then under the control of the Kuomintang Party, intervened in the arbitration at The Hague through the Taiwan Society of International Law (TSIL). Then President Ma Ying-jeou of Taiwan, who was also the head of the Kuomintang Party, was a former president of the TSIL. President Ma holds a PhD in Law from Harvard University where he specialized in the Law of the Sea.


The main claim of the TSIL, acting upon authority of Taiwan and the Kuomintang Party, is that Itu Aba is a habitable island entitled to a 200-nautical mile EEZ. The TSIL claimed an EEZ for Itu Aba solely in accordance with Unclos. In its submissions to the arbitral tribunal, the TSIL never used or even mentioned the term “historical rights” to claim an EEZ or any maritime zone for Itu Aba. The Kuomin-tang Party, the inventor of the nine-dash line, faithfully adhered to its original interpretation that the nine-dash line is a claim to islands and whatever maritime zones international law confers upon such islands. The Kuomin-tang Party never intended the nine-dash line as a historical claim to waters and resources beyond what international law allows.

In fact, earlier in September 2014, then President Ma, as head of the Taiwan government, had declared that the nine-dash line was a claim only to islands and their adjacent territorial seas. President Ma categorically stated that “there were no other so-called claims to sea regions.” President Ma, a true believer in the Law of the Sea, maintained the original intent of the nine-dash line and refused to expand it in violation of Unclos.

In contrast, China under the CCP claims “historical rights” under the nine-dash line to waters and resources beyond what international law, in particular Unclos, allows. China under the CCP has gone rogue, unlawfully usurping the EEZs of five Asean coastal states which under Unclos have the inherent right to their own EEZs.

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TAGS: Antonio T. Carpio, Crosscurrents, Kuomintang Party, Maritime Dispute, Nine-Dash Line, PH-China relations, South China Sea, Taiwan Society of International Law, TSIL, West Philippine Sea
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