As Japan and Philippines seek closer defence ties, could trilateral pact with US be next?

As the Philippines seeks to deepen its security cooperation with Japan days after granting the US greater access to its military facilities, some observers say a trilateral security alliance would be a logical next step amid concerns over China's growing power in the region.

President Ferdinand Marcos Jnr and Japanese Prime Minister Fumio Kishida signed a proposed agreement in Tokyo on Sunday that would permit the two nations' armed forces to cooperate on disaster relief, a measure widely seen as a stepping stone towards a pact that will allow the deployment of military units on each other's territory.

The move came as Marcos earlier this month granted US forces greater access to Philippine military facilities, a decision that China was quick to criticise on the grounds that it undermined regional stability and raised tensions.

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In anticipation of more criticism from Beijing, Marcos was keen to underline that his government would be cautious in pushing ahead with any new security arrangement with Tokyo, "because we do not want to appear provocative".

With tensions in the region increasing, notably over the future of Taiwan, experts said Japan was likely to want to forge closer ties between the two nations' militaries sooner rather than later.

"In many ways, the Philippines is the perfect ally for Japan as Manila is facing many of the same challenges from Beijing as Tokyo is," said Yakov Zinberg, a professor of international relations at Tokyo's Kokushikan University.

"Both nations are locked into territorial disputes with China - the Philippines over some of the atolls in the South China Sea and Japan over the Senkaku Islands in the East China Sea - and that in many ways bring them together," he said. Beijing claims the Senkaku archipelago as its sovereign territory which it calls the Diaoyu Islands.

Expanding ties in the region is also important for Tokyo and Washington, and the idea of a trilateral security alliance that includes the US "makes complete sense". Zinberg said that it may also form the basis for an expanded arrangement that brings in other nations with concerns about the growing power - and willingness to use that power - of China.

Stephen Nagy, an associate professor of international relations at Tokyo's International Christian University, said the key consideration for both governments was Taiwan.

"A military partnership with the Philippines will enable it to serve as a base for power projection and deterrence against a third country," Nagy said. "Manila has already signed a pact with the US to that effect and another agreement with Tokyo will serve to make this a trilateral agreement."

The Philippines plays a very important geopolitical role in the South China Sea, regional sea lanes and, critically, in the security of Taiwan, he said.

"Manila is concerned about a contingency involving Taiwan and the impact that any conflict would have on sea lanes, but also the impact on the wider region if [mainland] China is successful in an attack on Taiwan," Nagy added.

While Marcos has stated his policy is to be "a friend of everyone, an enemy of no one", that position may become harder to sustain. The Philippines has had a long and storied relationship with the US, while there has been deep resentment at how China has occupied islands and atolls in the South China Sea, as well as surrounding fishing waters, that have previously been considered part of the Philippines.

Manila had no response when hundreds of Chinese fishing boats crowded one of the small islets last year, forcing Filipino fishermen to leave the area. Hostilities towards Beijing took another turn, following reports the crew of a Philippine Coast Guard ship were temporarily blinded earlier this month when a "military grade" laser was aimed at their vessel by a Chinese Coast Guard cutter off Thomas Shoal, 195km off Palawan Province.

Japan has already provided help in the form of naval patrol boats and communications equipment, Nagy pointed out, with the new security arrangement meaning that more such aid is likely to be forthcoming in the future.

"Japan will try to enhance the Philippines' capacity in the key area of maritime defence, communications, its coastguard capabilities, in joint training and managing 'grey zone' situations," he said. "I am expecting more military exchanges between the two nations, although I do not believe the arrangement will go as far as Tokyo providing Manila with arms."

This article originally appeared on the South China Morning Post (SCMP).

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