The Basic View on the Sovereignty over the Senkaku Islands
There is no doubt that the Senkaku Islands are clearly an inherent part of the territory of Japan, in light of historical facts and based upon international law. Indeed, the Senkaku Islands are under the valid control of Japan. There exists no issue of territorial sovereignty to be resolved concerning the Senkaku Islands.
The Senkaku Islands are not included in the territory which Japan renounced under Article II of the San Francisco Peace Treaty, which came into effect in April 1952 and legally demarcated Japan's territory after World War II. They were placed under the administration of the United States of America as part of the Nansei Shoto Islands, in accordance with Article III of the said treaty, and were included in the areas whose administrative rights were reverted to Japan in accordance with the Agreement Between Japan and the United States of America Concerning the Ryukyu Islands and the Daito Islands, which came into force in May 1972. The facts outlined herein clearly indicate the status of the Senkaku Islands as being part of the territory of Japan.
Historically, the Senkaku Islands have continuously been an integral part of the Nansei Shoto Islands, which are the territory of Japan. From 1885 on, surveys of the Senkaku Islands were thoroughly carried out by the Government of Japan through the agencies of Okinawa Prefecture and by way of other methods. Through these surveys, it was confirmed that the Senkaku Islands had been uninhabited and showed no trace of having been under the control of the Qing Dynasty of China. Based on this confirmation, the Government of Japan made a Cabinet Decision on 14 January 1895 to erect a marker on the Islands to formally incorporate the Senkaku Islands into the territory of Japan.
Moreover, the Senkaku Islands were neither part of Taiwan nor part of the Pescadores Islands, which were ceded to Japan from the Qing Dynasty of China in accordance with Article 2 of the Treaty of Peace signed at Shimonoseki, which came into effect in May of 1895. The fact that China expressed no objection to the status of the Islands being under the administration of the United States under Article III of the San Francisco Peace Treaty clearly indicates that China did not consider the Senkaku Islands as part of Taiwan. The Republic of China (Taiwan) recognized the San Francisco Peace Treaty in the Sino-Japanese Peace Treaty, which came into effect in August 1952.
The Government of China and the Taiwanese authorities only began making their own assertions on territorial sovereignty over the Senkaku Islands in the 1970s, when the islands attracted attention after a United Nations agency conducted an academic survey in the autumn of 1968, which indicated the possibility of the existence of petroleum resources in the East China Sea. None of the arguments that the Chinese government or Taiwanese authorities have presented on historical, geographic or geological grounds is valid evidence under international law to support China’s own assertions of its territorial sovereignty over the Senkaku Islands.