The China - US War Prevention Through Japan’s Lens

In a recent interview, Hudson Institute’s Japan Chair Masashi Murano elaborated on a lot of long-standing concerns and answered some important questions. It caught our attention because (1) his new Japanese-language book Preventing a US-China War provides an inside look at the deterrence landscape in the Indo-Pacific, the future of US-Japan cooperation, and China’s preparations for war, and (2) the timing of the publish.

It is known that many books of similar domain interests have been published, but this one marks a shift in the national security mindset of Japan’s elites that had begun years ago but only become more noticeable recently. From an Asian point of view, America’s strategic repositioning around the first island chain was a direct function of China’s increasing military capabilities in both quality and quantity and had already begun during the Biden admin.

 

Context:

I. China’s Asymmetric Threat

· Nuclear Expansion: China is rapidly modernizing its nuclear arsenal, projected to reach 1,000 warheads by 2030 (up from 600 in 2024), including hypersonic missiles and silo-based ICBMs . This aims to control escalation in a Taiwan contingency.

· Conventional Capabilities: China’s navy (PLAN) is the world’s largest (370 ships), with plans to expand to 435 by 2030. Its defense industrial base enables mass production of advanced systems.

· Doctrine Shift: Moving from "minimum deterrence" to a "lean and effective" strategy, emphasizing second-strike capability and intra-war coercion .

II. U.S.-Japan Alliance: Critical Gaps and Priorities

· Defense Posture:

a. Base Vulnerability: Japanese bases (e.g., Iwakuni) are susceptible to Chinese missile strikes. Hardening infrastructure (shelters, rapid-repair systems) and dispersal tactics are urgent .

b. Spending Challenges: Japan’s 5-year defense plan (¥43 trillion) is undermined by yen depreciation (vs. 2022’s 108¥/$ rate). Purchasing power for U.S. equipment (e.g., F-35s) has eroded, necessitating budget revisions.

· Command Integration:

a. Japan’s new Joint Operations Command (JJOC) lacks full integration of C4ISR systems. Intelligence-sharing with the U.S. is hampered by Tokyo’s weak information security protocols .

· Role of U.S. Bases:

a. CSIS War Game: China succeeded in invading Taiwan only when Japan denied U.S. base access. Bases in Japan enable efficient sorties; alternatives (e.g., Guam) reduce strike effectiveness by 30–50% .

b. Political Risk: Japan must publicly debate the trade-off: short-term base-targeting risk vs. long-term catastrophe if Taiwan falls and the alliance collapses .

 

III. Deterrence Strategies: Balancing Escalation

· Intra-War Deterrence: Ukraine’s "salami-slicing" tactics (gradually expanding strikes on Russia) demonstrate how to test red lines while securing Western arms support. Key lessons:

· Legitimacy Matters: International backing enables escalation control.

· Independent ISR: Japan must develop its own surveillance/targeting to prove operational feasibility to hesitant allies.

· Avoiding Overcorrection: The U.S. risks excessive restraint post-Iraq/Afghanistan. Murano warns against underreacting to China due to "wars of choice" trauma .

IV. Coalition-Building: Limits and Opportunities

· Japan-South Korea-U.S. Trilateral:

Continues here