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Where are the Senkaku islands and why are they a source of dispute?

The Senkaku is a group of five small islands in the East China Sea about 170km north west of the Japanese island of Ishigaki. The islands are controlled by Japan but claimed by China, which calls them the Diaoyu, and also by Taiwan, which calls them the Diaoyutai. Ownership of the islands could give control of rich fishing grounds in the area and potentially of oil and gas resources in the area.

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Why is sovereignty over the group disputed?

The rival claims are based on differing interpretations of the islands’ history.

Japan legally incorporated the uninhabited Senkaku Islands into its southern prefecture of Okinawa in 1895, saying surveys over the previous 10 years showed they were terra nullius – land belonging to nobody. Japanese people lived and worked on the biggest island on the group until late in the second world war. It later came under US occupation along with the rest of Okinawa and was returned to Japanese control in 1971.

China and Taiwan both argue that historical documents show the islands are actually part of Taiwan (which China claims is also part of its territory). They say Japan illegally seized control of them under cover of the 1894-95 Sino-Japanese war. This makes the islands an emotional symbol of the bullying China suffered at the hands of foreign powers in the 19th and 20th centuries. But one weakness of Beijing and Taipei’s case is that they did not challenge Japan’s sovereignty claim until after UN surveys in the late 1960s suggested the area could be rich in oil.

Why has the issue flared up now?

China and Japan basically agreed to put the dispute aside when they resumed diplomatic relations in 1972. In order to avoid friction with China, Japan’s central government in 2003 rented three of the islands from their private owner, blocking landings on them by nationalist activists and leaving them undeveloped.

However, in recent years China has begun to use state vessels to challenge Japan’s effective control of the group. Japan’s arrest of a Chinese fishing boat captain who clashed with its coastguard in 2010 further raised tensions.

This year, the nationalist governor of Tokyo launched an effort to buy the three islands for development. In order to prevent this, Japan’s central government bought them instead. While Japanese officials insist the move is an attempt to maintain the status quo, Beijing has denounced it as an illegal provocation.

The Financial Times Limited 2012