On January 15, Japan's government signed an agreement with Manila to build boathouses and slipways for the Philippine Navy's inflatable patrol boats. It is a small structure by the standards of great-power competition — concrete, steel roofing, a place to store boats out of the weather. It is also the first infrastructure project ever delivered under Japan's Official Security Assistance program, the mechanism Tokyo created in 2023 to fund the militaries and coast guards of partner countries directly, rather than route everything through civilian aid.
OSA started in April 2023 with four recipients: Bangladesh, Fiji, Malaysia and the Philippines. By 2025, Thailand, Sri Lanka, Tonga, Timor-Leste and Papua New Guinea had joined the list. Japan has delivered two patrol boats to Indonesia, opened working-level defense consultations with Jakarta, and is discussing co-producing frigates with the Indonesian navy. None of this involves Japanese troops. It involves boats, radars, training, and boathouses — capacity built into other countries' own forces.
The civilian side of the ledger is growing at the same time. In April, the Japan International Cooperation Agency committed up to $1.5 billion to LEAP 2, an infrastructure fund managed by the Asian Development Bank rather than by Japan alone. That detail matters more than the amount. Where China's Belt and Road typically means a bilateral loan from a Chinese policy bank, Japan increasingly channels money through the ADB, the World Bank, or the AIIB — vehicles with shared oversight and shared blame if a project goes wrong.
Japan isn't trying to outspend China's Belt and Road. It's building where Belt and Road generally doesn't: coast guards, navies, maritime law enforcement.
Is Tokyo replacing Beijing's influence? Not in the aggregate — China still lends and builds at a scale Japan doesn't try to match, and Chinese-built ports, railways and power plants remain fixtures across the region. Japan's growth is narrower and more deliberate: maritime security equipment, coast guard training, and co-financed infrastructure with a multilateral name attached. Those are largely categories Belt and Road never prioritized, which is why Vietnam, the Philippines, Indonesia and Bangladesh can take Japanese patrol boats and Chinese-financed railways in the same year without treating it as a contradiction.
The appeal to these governments is fairly plain. Japanese financing rarely carries the debt-sustainability warnings that follow large Chinese loans. Japanese firms have operated manufacturing plants in Southeast Asia for decades, which gives Tokyo a commercial relationship most security partners lack. And OSA lets a country upgrade its coast guard without the political cost of a formal alliance or a US base agreement — a version of hedging that suits Hanoi and Jakarta as much as it suits Tokyo.
Whether Japan can lead without deploying its own military is really a question about what "leading" means now. Japan's post-war constitution still constrains what its own forces can do abroad. What it doesn't constrain is funding someone else's boathouse, someone else's patrol boat, someone else's frigate program. That is a smaller kind of leadership than Washington's or Beijing's. It is also one nobody in the region seems to be turning down.