Taipei recently launched a “freedom of navigation” operation in the western Pacific to challenge Japan’s claim to a 200-nautical-mile exclusive economic zone around Okinotorishima, an atoll located 950 nautical miles south of Tokyo and 850 nautical miles east of Taiwan. Two Taiwanese government ships, possibly escorted by a warship, have been sent to the Japanese-claimed waters—where the Japan Coast Guard detained a Taiwanese fishing boat on April 25—to demonstrate Taipei’s determination to protect Taiwanese fishery rights.

Taipei’s reaction runs counter to its own security. It has joined Beijing (and Seoul) in challenging Tokyo’s claim that Okinotorishima is an island entitled to a full exclusive economic zone (EEZ) as defined by the UN Convention on the Law of the Sea (UNCLOS). Beijing and now Taipei insist that Okinotorishima falls under the UNCLOS category of rocks “which cannot sustain human habitation or economic life of their own,” and therefore has no EEZ or continental shelf. Located between Guam and Taiwan, Okinotorishima has played an important role for the security of Taiwan. Beijing therefore wants to deny Japan’s jurisdiction over the waters around Okinotorishima in order to conduct scientific surveys necessary for submarine operations without Tokyo’s permission.

In case of a military threat to Taiwan, the waters around Japan’s southernmost atoll would become a maritime bridgehead from which the U.S. Seventh Fleet could project power to support Taiwan. In other words, those waters are where the Chinese People’s Liberation Army Navy would conduct anti-access/area-denial operations and the Japan Maritime Self-Defense Force would conduct sea control operations to ensure U.S. freedom of action. Taipei’s “freedom of navigation” operation, by implicitly supporting Beijing’s right to conduct surveys in the waters around Okinotorishima without Tokyo’s approval, are therefore against Taiwan’s own strategic interests.

The timing was unfortunate, too. A decision from the international tribunal deciding a case between Manila and Beijing over the South China Sea dispute is expected in a few weeks. Taipei is concerned that the court might rule on whether the largest natural islet in the South China Sea—the Taiwan-occupied Itu Aba (Taiping) Island—is a rock or a full island under UNCLOS, and as a result might be seeking to highlight how Itu Aba differs from a tiny atoll like Okinotorishima. But Taipei’s move also opens room for Beijing to avert international criticism of its land reclamation in the South China Sea by criticizing Tokyo for not preserving UNCLOS provisions.

Little is known about what triggered Taipei’s unusually strong reaction to the April 25 arrest of Taiwanese fishermen, but it is possible that the government of outgoing President Ma Ying-jeou hoped to embarrass President-elect Tsai Ing-wen, who is seen as being pro-Japan. Tsai’s Democratic Progressive Party (DPP) has actually denounced Tokyo for detaining the Taiwanese fishermen. But Joseph Wu, who will become secretary-general of the National Security Council under Tsai, told reporters that sending armed vessels to protect Taiwanese fishing boats requires “careful consideration.”

This is a test for the strategic partnership between Prime Minister Shinzo Abe and President Tsai, and between Japan’s ruling Liberal Democratic Party and the DPP. Given Taipei’s interest in negotiating an agreement guaranteeing the right of Taiwanese fishermen to operate in the waters around Okinotorishima, one way to resolve this dispute would be to conclude a civil fishery agreement in which Taipei implicitly acknowledged Japan’s sovereign rights while gaining access to fishery resources. Such an agreement might be justified as a joint effort to prevent overfishing of tuna under the Convention on the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean—one of the few international conventions to which Taipei is a party.

Tokyo and Taipei should turn this difficult moment into a chance to conduct unofficial maritime security dialogue. Some Taiwanese are concerned about Japan’s plan to provide patrol ships to the Philippine Coast Guard for fear that those ships will be used to suppress Taiwanese fishing boats in disputed waters in the South China Sea. There is an urgent for Tokyo and Taipei need to narrow their misunderstanding of each other’s maritime security policies. Taiwan and Japan can also cooperate in promoting Taipei’s accession to more international fishery treaties. Meanwhile, the two parties should review the implementation of the 2013 civil fishery agreement in the East China Sea to prevent fishermen from operating against the cooperative spirit of the agreement.

About Tetsuo Kotani

Tetsuo Kotani is a senior fellow at the Japan Institute of International Affairs (JIIA) and also a lecturer at Hosei University. He was a visiting scholar at Japan Chair at the Center for Strategic and International Studies (CSIS) Mr. Kotani’s research focus is the US-Japan alliance and maritime security, and he won the 2003 Japanese Defense Minister Prize.