History & Culture / East Asia

What is the Diaoyu/Senkaku islands dispute about?

by Isabella Chua
Length 6 min

Somewhere in the East China Sea lies a chain of uninhabited islands that go by different names. To the Chinese, they are known as the Diaoyu Dao. Taiwan calls it the Diaoyutai Islets, and Japan calls it the Senkaku Islands. All three entities believe they have a legitimate claim to the islands. What exactly led to this situation?

What are these islands?

The archipelago comprises of eight islands in total. Geologically, that amounts to five islands and three rocks. They have been uninhabited ever since Koga Tatsuhiroa — a businessman trading in dried bonito — and his employees left the islands in 1940. These days, any sightings of ships or aircraft near the islands can quickly trigger political tension and scrutiny.

an illustration of the eight islands that make up the senkaku or diaoyu islands.

Currently, the islands are under Japan’s administrative control. Through the 1971 Okinawa Reversion Treaty, the US returned the Ryukyu Islands—which included the disputed islands—to Japan. However, the US made it clear that the transfer of the right of administration does not equate to the transfer of sovereignty. Hence, the sovereignty of the islands continues to be contested.

With less than seven square kilometres in total land mass, the islands have little value. Where the islands are valuable, is that the victorious claimant could, under international law, gain exclusive economic rights to nearly 20,000 square nautical miles to the surrounding seas and seabed.

Beneath the waters lie a potential treasure trove of natural gas, oil, and fishes. In fact, Japan accused China of only caring about the islands after an academic survey of the East China Sea done in 1968 found the presence of oil and gas reserves near the islands.


Why is there a dispute?

Fundamentally, the dispute boils down to two unresolved disagreements between China and Japan.

Firstly, the islands were not explicitly mentioned in the territories that Japan had to surrender to China after the Second World War. From China’s perspective, Japan is not honouring the wartime treaties, such as the 1943 Cairo Declaration. The declaration stated that Japan “shall be stripped of all the islands in the Pacific which she has seized or occupied since the beginning of the first World War in 1914” as a precondition of their surrender.

Taiwan agrees. Taiwan believes that the islands are part of Chinese territory, and an inseparable part of Yilan, Taiwan. But from Japan’s perspective, the treaty terms do not apply to the islands, since they were already incorporated as Japanese territory in 1895.

This brings us to the second point of contention, which questions the validity of Japan’s incorporation of the islands on the basis of them being terra nullius. Terra nullius is land that is uninhabited and unclaimed by anyone.

According to Japan, after surveying that the islands were terra nullius in 1885, they formally incorporated them in 1895. Apart from the brief period between 1945 and 1972 when the United States took administrative control of the islands, the islands have always been Japanese territory.

China disagrees. They claim to have known of the islands’ existence since the Ming dynasty, some four centuries before Japan’s discovery. Their proof? Various maps and books created during the Ming and Qing dynasty have mentioned “Diaoyu” in their texts.

An overview of the key historical evidence from China, Japan, and Taiwan.

How has the dispute manifested?

The dispute has largely manifested in the form of tit-for-tat tactics between China and Japan, mostly in the form of vessel patrols near the islands. Both parties have been cautious about escalating the dispute, since the US would be obliged to come to Japan’s aid due to the Treaty of Mutual Cooperation and Security.

An overview of the events

However, the dispute goes beyond powerful entities fighting it out. It is very much about the people, who consider defending their countries’ claims as an act of patriotism.

Over the years, Japanese activists have sporadically landed on the islands to affirm Japan’s ownership of the islands. In China, there was an unprecedented show of unity with people from Hong Kong and Taiwan joining the Chinese in protesting against Japan’s decision to purchase three of the islands in 2012, and calling for the return of the islands to China.

Chinese protestors in Shenyang holding portraits of Mao Zedong in the 2012 anti-Japanese demonstration.
Chinese demonstrators in Shenyang. Mao Zedong was a common motif in the 2012 anti-Japan demonstrations. The Chinese used it to criticise the soft stance of current leaders in dealing with the dispute compared to Mao’s resistance against the Japanese during the Second World War. Credits: By Shujenchang - Own work, CCB BY-SA 3.0), https://commons.wikimedia.org/wiki/File:Shenyang_918_Anti-Japan_Procession_1.jpg

This outward display of patriotism may have added a layer of complexity to the dispute, as the respective leaders were pressured to present a tougher front when dealing with the dispute. For example, Chinese premier Wen Jiabao turned down a meeting with Japan’s Finance Minister Naoto Kan in 2010, in response to Japan’s arrest of a Chinese fishing crew and captain.


What are the latest developments?

Last year, Japan and China celebrated the 40th anniversary of the Treaty of Peace and Friendship. In his congratulatory message, Japan’s Prime Minister Shinzo Abe said he was “very pleased to have Japan-China relations return to a normal path”. Echoing his sentiment of goodwill, Chinese Premier Li Keqiang expressed a desire to “promote lasting, sound and stable relations.”

a picture of shinzo abe and xi jinping shaking hands in front of their respective countries' flags.
Credits: Prime Minister's Office of Japan, CC BY 4.0, https://commons.wikimedia.org/wiki/File:Shinz%C5%8D_Abe_and_Xi_Jinping_(November_2017).jpg

During the G20 summit this year, the issue of the Diaoyu/Senkaku islands was broached. In response to Shinzo Abe cautioning about China’s military build-up in the East China Sea, China President Xi Jinping reaffirmed China’s default position. However, the two leaders did agree to have “permanent and close communication as eternal neighbours”.

While these developments show that both countries are open to dialogue, the island dispute will probably take a backseat in light of the ongoing trade dispute between China and the US. Moreover, the island disputes have historically been characterised by alternating periods of relative calm and aggressive posturing. Peace in the East China Sea for now does not guarantee calm waters in the future.