The longstanding territorial dispute over the Diaoyutai Islands has once again flared up. The Japanese government's recent unilateral move on Sept. 11, 2012 to "nationalize" three of the islands, known as "Senkaku" in Japanese, through a purported "purchase" has reignited tensions in East Asia. But while most attention has focused on the standoff between China and Japan, the Diaoyutai Islands actually form an inherent part of the territory of the Republic of China (Taiwan) based on the islands' geographical location, geological structure, relevant historical evidence, and international law. Japan's claim over the islands simply does not stand up to close scrutiny.
Japan's claim of sovereignty over the Diaoyutai Islands by virtue of "discovery-occupation" under international law is invalid ab initio (from the onset), as such claims can only be made to terra nullius (land without owner).
The Diaoyutai Islands were first discovered, named, and used by China during the Ming Dynasty (1368-1644). Chinese envoys at the time used the islands as navigation posts en route to the Ryukyu Kingdom (now Okinawa), a vassal state of China. The islands were also incorporated into Ming China's coastal defense system and patrolled by Chinese naval forces against the invading Japanese pirates.
The most authoritative historical records supporting the Chinese claim are envoy mission records and official Taiwan gazetteers published during the Qing Dynasty (1644-1912). Envoy mission records specified the national boundary between China and Ryukyu Kingdom as heishuigou (or Black Water Trough, known today as the Okinawa Trough) and the Diaoyutai Islands, and listed the islands as within the "the boundary between China and foreign land."
Official gazetteers of Fujian Province and Taiwan Prefecture also listed territories under Taiwan, which included the Diaoyutai Islands. For example, Record of Missions to Taiwan Waters (1722) listed the patrol routes of the naval forces of Taiwan Prefecture, stating"in the seas north of Taiwan is an island called Diaoyutai where ten or more large ships may be anchored." Subsequently, the Revised Gazetteer of Taiwan Prefecture (1747), Continued Gazetteer of Taiwan Prefecture (1764), Pictorial Treatise of Taiwan Proper (1872) all included this reference. In Recompiled General Gazetteer of Fujian (1871), the Diaoyutai Island was further listed under Kavalan County (now Ilan County) of Taiwan. These local gazetteers' primary functions were to "record history, assist governance, and inform the populace." These official documents demonstrate Qing China's long and continuous effective control over the islands as part of Taiwan prior to 1895.
Today, the Japanese government asserts that from 1885 on, it repeatedly conducted on-site surveys which confirmed that the islands were uninhabited and there were no signs of control by the Qing Empire. "It therefore made a Cabinet Decision on January 14 1895 to formally incorporate the islands." However, old Meiji period documents unearthed from Japanese archives demonstrate that the Meiji government acknowledged Chinese ownership of the islands in 1885.
In October 1885, following the first onsite investigation, then Foreign Minister Inoue Kaoru and Foreign Ministry Public Communications Director Asada Tokunori described the islands as "close to the Chinese border... next to Taiwan and belonging to China"(emphasis added) and "at this time, if we were to publicly place national markers, this must necessarily invite China's suspicion...."
In November 1885, Okinawa Magistrate Nishimura Sutezo confirmed "since this matter is not unrelated to China, if problems do arise I would be in grave repentance for my responsibility."
Ten years later, in May 1894, Okinawa Governor Narahara Shigeru wrote to the Home Ministry confirming "...no investigations of the islands took place since mid-1885..."
In August 1894, the Sino-Japanese War broke out. On Sept. 17, Japan defeated China's Beiyang Naval Fleet. On Oct. 24, Japan crossed the Yalu River and invaded China. By Nov. 21, Japan had captured the Chinese city Port Arthur. In December 1894, the Japanese Home Ministry stated that the incorporation of the disputed islands "involved negotiations with China... but the situation today is greatly different from back then." Japan accordingly incorporated the islands based on a cabinet decision of Jan. 14, 1895 amid the ongoing war. The cabinet decision was marked "Confidential" and, contrary to established convention, was never publicly announced.