China's Haijing 2502 patrol vessel sails into waters near the disputed Senkaku islands in the East China Sea on November 6, 2016. China also claims the islands, which it refers to as Diaoyu. Photo: AFP / Japan Coast Guard

The cluster of disputes between Japan and China in the East China Sea threatens regional and even world peace. Moreover, their dispute over the Senkaku/Dioayutai rocks is a bellwether of their relations because it involves issues of power, sovereignty, national pride and bitter history.

Japan is considering strengthening its military presence near the disputed features it administers as the Senkakus. But they are also actively claimed as the Diaoyutai by China, which has increased deployment of its coast guard vessels in the territorial seas extending 12 nautical miles around the features.

Tokyo has severely criticized Beijing for its behavior there and these issues have become “internationalized,” with the US supporting its ally Japan.

The narrative in Japan is that the Senkaku features have always belonged to it and that China is trying to change the status quo by coercion. But the narrative in China is that Japan used force to acquire the features and that they are a part of China and should be returned to it.

Indeed, from China’s perspective it is Japan that changed the status quo – which was more or less “working” – by “nationalizing” them in 2012 and then aggressively consolidating its position by excluding China’s fishing boats and coast guard vessels from its rightful waters.

Beijing justifies its vessels’ presence by saying that the features are its “inherent territory”; that Japanese boats are fishing illegally in China’s claimed territorial seas; and China is trying to prevent that. From a legal perspective, China believes it is demonstrating that it is not acquiescing to Japan’s claim.

These features are not especially valuable economically by themselves. Indeed they are likely entitled legally only to 12nm territorial seas and a 24nm contiguous zone – not a continental shelf or 200nm exclusive economic zone.

It is unclear if they can legally be used as base points in defining a boundary with China. Japan says they can. China says they cannot. These legal differences result in a large area of overlapping claims to waters and seabed in the East China Sea, adding ownership of valuable seabed metals and hydrocarbons to the bitter sovereignty dispute.

The problem is that many Chinese view this dispute and its outcome as a reckoning based on their historical experience with Japan. For them, it is rather simple. Japan stole the features by force when China was weak. Fifty years later Japan invaded its territory and horribly abused its people and culture prior to and during World War II.

China resisted and joined the eventually victorious anti-Japan coalition. Japan lost the war. It doesn’t get to keep territory it took by force and it should have been returned to China years ago – and would have been but for the manipulations of the US. China is now strong and wants them back.

This dispute is not just dangerous for the two protagonists. It threatens regional and perhaps world peace because the US could get drawn into a kinetic conflict between the two.

In response to pressure from Tokyo, Washington has repeatedly reaffirmed that the features come under the scope of the US-Japan Treaty of Mutual Cooperation and Security.

Japan and presumably China think the US will assist Japan “if territories under its administration [or its military forces defending them] come under armed attack.” To China, this is part of a conspiracy to encircle and contain it strategically.

Japan justifies its militarist response to increased “intrusions” of China’s coast guard vessels and its new law authorizing its coast guard “to take all necessary measures, including the use of weapons, when national sovereignty, sovereign rights, and jurisdiction are being illegally infringed upon by foreign organizations or individuals at sea.”

In response to that law, Japan has said its Maritime Self-Defense Force is authorized to use force to prevent foreigners from landing on the features.

Absent a UN Security Council mandate or a situation requiring an act of self-defense against a “grave use of force,” such use of force would probably violate international law. Nevertheless it is a common practice around the world. Ironically the most common targets of the use of excessive and deadly force against civilians are Chinese fishing boats and crews.

So far Japan has refrained from stationing troops on the disputed rocks themselves because this would almost certainly provoke a response from China. Despite American reassurances to Tokyo, it is not certain that the US would respond with force if Japan purposely provoked the response, and Japan knows this – or should.

In 2015 Japan planned to send Self-Defense Force ground troops and surface-to-air and anti-ship missiles to Ishigaki, Miyako and Amami-Oshima in Okinawa prefecture as close as 170 kilometers from the Senkakus. It is also preparing for the worst by investing in military assets designed to defend or reclaim remote islands.

Japan’s response is disproportionate to the “threat” and takes the cycle to the next level – deployment of military assets. It is of course its right to militarize its sovereign territory. But the signal it sends is that it is preparing to use force.

Indeed, Beijing perceives that Japan’s military installations will be able to target Chinese military assets in the East China Sea. This rings alarm bells in Beijing because historically that sea facilitated foreign invasion. This and protection of its vital sea lanes and nuclear-armed submarines is why Beijing has tried to exert control in the South China and East China Seas.

So Japan’s military buildup in its extreme southwest islands worries China not because of the Senkakus/Diaoyutai dispute per se but because it perceives that Japan (in coordination with the US) is preparing to choke off passage of China’s aircraft and warships through the archipelago’s straits into the Pacific.

The US in coordination with Japan supposedly also has an underwater sonar array along the Ryukyu Archipelago that can detect submarines for targeting.

In the event of war, China would need to move its assets into the Pacific Ocean, or they would be bottled up in the South and East China Seas where they can more easily be targeted and neutralized. So further militarization of this spat over rocks will only lead to a tit-for-tat cycle that will draw in the US and maybe others in a muscle-flexing test of wills that energizes nationalists in both countries, making the situation all the more dangerous.

The point is that Japan’s militarist response – no matter how it publicly spins it – will raise the problem to the next level and invite a similar response from China. And that is a very bad idea.

Mark Valencia is a non-resident senior research fellow at the Huayang Institute for Maritime Cooperation and Ocean Governance.