ONE of the Philippines’ closest regional partners, Japan, recently doubled its defense expenditure under a new government led by Prime Minister Sanae Takaichi in response to what it says is the most complex and dangerous security environment since World War II. The move is expected to have a major positive impact on the Philippines as it continues to deal with Chinese acts of aggression.
Following the electoral success of Takaichi and her Liberal Democratic Party last month, there is now greater momentum for Japan to implement its “Free and Open Indo-Pacific” (FOIP) vision, an approach supported by the Philippines and one that would enhance the region’s long-term security and prosperity.
FOIP was a concept introduced almost a decade ago by Japan’s then-prime minister Shinzō Abe. It rests on key principles, including opposition to any one actor seeking to undermine the rules-based order, infringe on national sovereignty, or impact freedom of navigation.
During the Honolulu Defense Forum in January, Japan’s Defense Minister Shinjirō Koizumi confronted the challenges the Indo-Pacific faces and the roles the region’s key powers can play in keeping the region free and open. He stressed Japan’s desire to continue “fundamentally reinforcing” both its own and the wider region’s defense capabilities.
This position aligns with the US’ new national defense strategy that aims to prevent China from dominating the Indo-Pacific. In particular, it says the US will construct a “strong denial defense” along the so-called First Island Chain, which stretches from Japan, Taiwan and the Philippines to the Malaysian peninsula. In December 2025, US President Donald Trump’s administration approved $11.1 billion in arms support for Taiwan, the largest such package to date. For nations and territories under direct threat, like Taiwan, this increasing support from nations such as Japan and the US is significant.
Growing regional threats have necessitated the coming together of the Indo-Pacific’s key players to boost collaboration in sectors that include defense. The Philippines is playing an increasing role in this security theater, and can help shape how the region should respond to threats, not least those in the West Philippine Sea.
Tokyo is responding to these threats accordingly. It has assumed a leading role in enhancing regional responsiveness in close coordination with its partners. Japan’s doubling of defense spending under a new record budget would provide a greater regional collaboration boost, helping shield the Indo-Pacific from rogue actors.
Once approved, Japan’s new defense budget will bolster multirange strike-back capability and coastal defenses with surface-to-ship missiles and increase unmanned assets for both surveillance and strike capability.
The Philippines has also put defense spending into high gear after a year of multiple Chinese incursions into its territory and provocative acts in the West Philippine Sea.
Manila recognizes Tokyo’s emergence as a vital defense partner, sharing significant official security assistance (OSA), including coastal radar systems, marine vessels, defense equipment, and aerial surveillance technology critical for domain awareness. At the same time, it looks forward to exploring other areas for greater assistance under Koizumi’s push to strengthen Japan’s “top-level sales diplomacy” toward like-minded nations.
Together, the Philippines and Japan stand at the forefront of the Indo-Pacific. Bilateral ties have long been strong, but were recently raised to the next level with the signing of a new defense pact that will have major positive ramifications in joint training exercises.
This pact enables the tax-free provision of key supplies, including ammunition, fuel and food, when conducting military exercises, which have continued to grow in scope.
Japan also announced additional security and economic development assistance to the Philippines. This builds on wider agreements already in effect, including a reciprocal access agreement (RAA) that began last September, which permits the nations to operate in each other’s respective sovereign territory, paving the way for new joint military exercises, the first of which took place in October.
This evolving quasi-security alliance reduces prior impediments to collaboration and normalizes bilateral military interactions, enhancing respective capability.
In January, a Coast Guard aircraft operating a routine patrol near Scarborough Shoal in the West Philippine Sea was “repeatedly challenged” by a Chinese navy vessel. This incident took place within the Philippines’ exclusive economic zone, where several Chinese vessels are said to have been operating and in an area of significant importance to global trade.
This fits a historic pattern, but the frequency of these interactions has increased dramatically in recent times. Moreover, infringements into long-established economic zones in breach of international law could have negative ramifications for Manila’s recent announcement of its first natural gas discovery in more than a decade within such a zone.
As China’s war games grow in scale, both unilateral and joint exercises by the Philippines and Japan will also need to develop — something the recent defense pact makes possible.
Multidomain threats require a multipronged approach between the region’s key players to restore international order in the maritime commons and to ensure the Indo-Pacific’s long-term prosperity.
The author is a retired rear admiral and maritime security expert who once served as the vice commander of the Philippine Navy.
