China’s latest move at Scarborough Shoal may appear routine. By tightening access controls with a barrier and layered vessel presence, Beijing has once again signaled that its strategy aims to normalize its presence along key maritime lanes.
Yet this move signals a broader shift in the Indo-Pacific, with Japan emerging as its center. The United States, Australia, and the Philippines recently conducted joint maritime drills in the South China Sea.
The Philippine Department of National Defense also announced that the upcoming Balikatan exercises will involve more than 17,000 troops, with Japan participating in live-fire drills for the first time.
Australia and Japan also finalized contracts to proceed with a major frigate program, further integrating their defense industrial bases.
Taken together, these developments reveal a structural shift in the Indo-Pacific, one that is challenging the once-standardized Washington hub-and-spoke alliance approach. This shift represents a denser, more networked architecture in which Japan is emerging as the central connector.
It is the only regional actor simultaneously operating across alliance structures, minilateral security groupings and defense-industrial partnerships. No other actor currently combines these roles at a comparable scale.
For decades, regional security was anchored in a US-led hub-and-spokes alliance system. That system provided stability, but also limited how effectively allies could operate together without the US. Coordination was often routed through Washington, and operational integration between non-US partners remained shallow.
With great power competition centered in East Asia rather than in Eurasia, regional states have adapted their strategies to reflect this shift. China’s persistent and calibrated maritime coercion, characterized by coast guard patrols, maritime militia activity and now physical barriers, continues to challenge the sovereignty of many East and Southeast Asian states.
Japan is at the center of that shift. Its role is no longer confined to hosting US forces or providing rear-area support. Rather, it is becoming an active operational partner, a defense-industrial supplier and a political bridge linking different parts of the region’s emerging security network.
Its participation in Balikatan’s live-fire component signals this transition clearly. Japan is no longer just observing or supporting from the sidelines — it is increasingly willing to operate alongside Southeast Asian partners in more demanding scenarios.
Deterrence credibility depends not only on capabilities, but on the visible willingness to use them in coordinated ways. Even if conflict remains unlikely, the shift signals that regional states are becoming more willing to act collectively in defense of their own sovereignty.
Japan’s expanding defense-industrial role is reinforcing these ties in ways that go beyond exercises. The frigate agreement with Australia is not simply a procurement deal. It is part of a broader pattern in which Japan is helping to build capacity across the region, embedding itself more deeply in partners’ defense planning and long-term force structures.
This dual role — both operational and industrial — aligns closely with US strategic priorities, and Japan’s relationship with Washington has continued to strengthen.
Japanese strategy connects US alliance commitments to a wider set of regional actors while enabling those actors to strengthen their own capabilities and interoperability without abandoning their sovereignty or non-aligned traditions.
This role is also expanding into economic statecraft, including the US–Japan critical minerals framework, which aims to strengthen supply chain resilience and reduce dependence on Chinese processing.
To be sure, this is not an “Asian NATO,” nor does it replace US leadership. The US remains indispensable.
But the structure around it is becoming more distributed, shifting from bilateral relationships centered on Washington toward overlapping networks: US-Japan-Philippines, Japan-Australia, Australia-Philippines and increasingly broader combinations depending on the mission.
China’s strategy exploits gaps between allies, legal thresholds and the space between peacetime and conflict. A more networked deterrence architecture reduces those gaps, raising the costs of coercion not just by increasing the number of actors involved but by making their responses more coordinated and less predictable.
Constraints remain, and these exercises do not mean seamless interoperability. Defense-industrial cooperation takes time to scale. Political constraints, particularly in Southeast Asia, will continue to shape how far and how fast this network develops.
At the same time, the trajectory is clear. The Indo-Pacific is no longer relying solely on a US-centered system to manage security challenges. It is building something more flexible and potentially more resilient.
The question is no longer whether regional states can coordinate. It is whether they can translate this emerging network into a durable deterrent before China’s incremental advances solidify into the new status quo.
Christian Cerne is a master’s degree candidate in international & development studies at the Geneva Graduate Institute (IHEID)