The rolling thunder effects of being target locked: Why Japan-China tensions now shake the whole Indo-Pacific

JAPAN'S revelation that two Chinese J-15 fighter jets had “locked” their fire-control radar on Japanese F-15 aircraft over international waters near Okinawa is not just a bilateral dispute; it signals how Tokyo–Beijing tensions now have the potential to destabilise the entire Indo-Pacific region. This escalation is a warning of how one military encounter can send shockwaves through regional security.

“Radar lock” is not simply observation. In military terms, it is aiming a weapon system at an aircraft, indicating readiness to fire.

Tokyo immediately filed a diplomatic protest, calling the act “dangerous, unacceptable, and destabilising.”

For Japan, this was not merely an unfriendly encounter; it was a sign that relations with China have entered an increasingly precarious phase, where the margin for misinterpretation has narrowed to a sliver.

Why Radar Locking Is So Dangerous

Fire-control radar precisely tracks a target and calculates firing solutions. Unlike search radar, it does not scan broadly but locks onto a specific object.

A radar lock triggers cockpit alarms in the targeted aircraft. Pilots must act within seconds—deploying countermeasures, altering flight paths, and assessing potential missile threats.

Such incidents are among the most volatile military interactions short of combat, creating tense moments that risk miscalculation.

China conducted similar actions in 2013 when a Chinese vessel locked radar on a Japanese destroyer and a helicopter. The recurrence in 2025 suggests Beijing is increasingly willing to use high-risk signalling to assert dominance over contested maritime and aerial zones.

The Political Trigger: Taiwan and Japan's Shifting Posture

The timing of this incident was not random. Shortly beforehand, Prime Minister Sanae Takaichi was pressured in Japan’s Diet to clarify whether Taiwan’s security was linked to Japan’s survival. Under repeated questioning — and showing political inexperience in managing strategic ambiguity — she made a statement that Beijing interpreted as a new Japanese willingness to intervene if Taiwan were attacked.

Although Takaichi later softened her remarks, the damage was done. For China, Tokyo had crossed a symbolic line.

The radar lock must be viewed through this lens: a coercive warning to Japan not to deepen its political and military alignment with Taiwan and the United States.

Japan’s Strategic Response: Defence Recalibration Accelerates

Japan has long reconsidered its defence posture, but such incidents accelerate the trend. Tokyo is on track for record defence spending since World War II.

Recent investments include long-range strike missile capabilities, integration of Japanese and U.S. early-warning systems, strengthening the Self-Defence Force's presence in the Southwest Islands, and deepening interoperability with the U.S. Indo-Pacific Command.

The radar lock reinforces the perception among Japanese policymakers and the public that China is willing to use coercive tactics in peacetime — a threat that demands stronger deterrence capabilities.

The United States: The Silent but Critical Actor

Though Washington was not directly involved, its role is foundational. Under the U.S.–Japan Security Treaty, any attack on Japan obliges a U.S. response.

Fire-control radar locks, therefore, are never “just” bilateral incidents. They test U.S. credibility and willingness to deter Chinese aggression.

The United States is likely to respond by increasing joint patrols with Japan, enhancing early-warning and radar-sharing networks, tightening trilateral security coordination with Australia and South Korea and signalling publicly that aggression toward Japanese aircraft risks triggering Article 5-type responses.

For Washington, allowing such acts to go unchallenged may invite more assertive behaviour from Beijing across the Western Pacific.

ASEAN: The Uncomfortable Neighbour Caught Between Giants

Southeast Asia cannot simply stand by on the sidelines. Incidents similar to Japan’s radar lock encounter inevitably radiate outward, affecting every ASEAN member state.

First, there is the issue of strategic spillover into the South China Sea. If China grows accustomed to radar locking Japanese aircraft, similar tactics may be used against Malaysian, Vietnamese, or Philippine aircraft in the South China Sea.

China has already deployed military-grade lasers, water cannons, and aggressive intercepts. Radar locking would mark a dangerous escalation.

Second, ASEAN’s longstanding strategy of strategic diversification is now under pressure. For decades, ASEAN has practised strategic diversification — engaging China economically while relying on the United States and its allies for security reassurance.

But as Sino-Japanese and Sino-American tensions rise, the middle space ASEAN once occupied is shrinking. Strategic diversification is harder as both powers demand clearer alignment.

Third, heightened confrontation pushes Beijing toward a defensive posture, reducing its willingness to compromise with ASEAN on a South China Sea Code of Conduct (COC). Without a credible COC, Southeast Asia remains exposed to high-risk behaviour, such as radar locking.

Fourth, there is rising pressure on ASEAN to upgrade its air-sea preparedness. Most ASEAN air forces are not equipped to manage fire-control confrontations. If this behaviour spreads south, ASEAN’s operational vulnerabilities will become glaringly exposed.

Fifth, chairmanship in 2025 will be particularly significant. Malaysia’s central role becomes critical. Prime Minister Anwar Ibrahim must now steer ASEAN through a landscape marked by intensifying Sino-Japanese friction, Sino-American rivalry, and increasing regional militarisation.

Malaysia’s diplomatic capital — rooted in civilizational dialogue and balanced engagement — will be needed more than ever.

The Rolling Thunder Effect: How Escalation Accumulates

The true danger of radar lock incidents lies not in the single episode but in their cumulative impact. Think of them as similar to rolling thunder: each echo amplifies the next.

First, alliance dynamics are hardening. Japan moves even closer to the United States, Australia, and possibly South Korea.

China interprets this as encirclement, prompting further militarisation.

Second, rules of engagement are tightening. Pilots may be ordered to respond with their own locks, flares, or aggressive manoeuvres.

One error in judgment could cause a catastrophe.

Third, domestic politics in both Japan and China are becoming increasingly polarized. Japanese hawks gain momentum. Chinese nationalists push for stronger action. Both reinforce each other in a destabilizing feedback loop.

Fourth, ASEAN’s stability is becoming increasingly fragile. Southeast Asia becomes acutely vulnerable to spillover risks, especially in contested maritime zones.

Conclusion: Preventing a New Normal of Provocation

The radar lock near Okinawa is more than an isolated military encounter. It is a signal that East Asia is entering a more volatile era, where coercive signalling risks becoming normalized.

If such behaviour continues unchecked, the entire Indo-Pacific could face a dangerous future defined by aerial brinkmanship, shrinking diplomatic buffers, and heightened risk of inadvertent conflict.

For Japan, the United States, and ASEAN, the challenge is to prevent this new normal from taking root. The alternative is a region living under constant threat — where one radar lock could ignite a crisis none of Asia’s leaders truly wants.

Phar Kim Beng, PhD, is Professor of ASEAN Studies and Director of the Institute of Internationaliation and ASEAN Studies (IINTAS) at the International Islamic University Malaysia.

Luthfy Hamzah is Senior Research Fellow at IINTAS and a specialist in trade, political economy, and strategic diplomacy in Northeast Asia.

** The views and opinions expressed in this article are those of the author(s) and do not necessarily reflect the position of Astro AWANI.