Turbulent waters: The escalating row between Japan and China over the Senkaku/Diaoyu Islands has implications for us all

A tiny chain of five uninhabited islets and three barren rocks, hundreds of miles from land, might seem an unlikely prize. But with everything from oil revenues to regional clout at stake, the contretemps over an obscure archipelago known to Japan as the Senkaku and to China as the Diaoyu is cause for grave concern.

Beijing maintains that the islands were claimed by China in the 1300s; Tokyo says they were an international no man’s land until Japan took them over in 1895. The row has been rumbling since the 1970s, but the pressure has steadily increased in recent years as a newly rich China has sought to flex its regional muscles and extend its influence in the US-dominated Pacific.

Japan must bear responsibility for many recent flashpoints. Last year’s announcement by the Governor of Tokyo of plans to use public money to buy the islands from their private owner hardly aimed to defuse the tension. This time, though, it is China that has upped the ante – and how. Last weekend, Beijing declared a new “air defence identification zone” covering a swathe of the South China Sea, including the islands, requiring all aircraft entering the sector to submit flight plans or face “defensive emergency measures”. Even more provocatively, the area overlaps with one of Japan’s own air defence zones.

Sure enough, Tokyo’s response was swift and uncompromising. The Prime Minister, Shinzo Abe, derided the plan as “unenforceable” and “of no validity whatsoever”; and the two Japanese long-haul airlines which initially complied with Beijing’s demands were soon persuaded to withdraw their co-operation.

But it is the reaction of the US that is crucial here. Indeed, in the context not only of Washington’s post-war commitment to the defence of Japanese territory (which includes the Senkaku Islands), but also the recent foreign policy “pivot to Asia” (prompted by rising Chinese power), Beijing’s move looks like as much of a test of Barack Obama as of Mr Abe.

The answer was unequivocal. On Tuesday, the US flew two unarmed B52s through the zone without notifying the Chinese. The Pentagon claims that the flight was a long-planned training mission but the message is clear – particularly given that it came just days after the Defence Secretary, Chuck Hagel, branded Beijing’s move “a destabilising attempt to alter the status quo in the region” and stated explicitly that American military operations would not change.

Washington’s move was the right one. China cannot be allowed to throw its weight around; if Beijing has a case then it must be legally proven, not administered unilaterally at the point of a metaphorical bayonet. Equally, however, Japan has shown itself too ready to indulge in chest-beating of its own and Mr Abe at times exhibits disturbingly nationalist leanings. The US must be sure that, while maintaining regional balance, it does not endorse such posturing.

China’s economic rise inevitably brings disruption with it. And with both Beijing and Tokyo under growing domestic pressure for a show of strength abroad, the diplomatic task facing the US in Asia is as difficult and perilous as any. The Senkaku/Diaoyu are just a few distant rocks, but they may also be the fulcrum upon which one of the greatest challenges of 21st-century geopolitics will turn.