Overview
In early December 2025, China’s Liaoning aircraft carrier strike group sailed through waters near Japan’s southwest island chain and into the western Pacific, conducting roughly 100 take-offs and landings of J-15 fighters and helicopters over two days between Okinawa’s main island and Minamidaito and then east of Kikai Island. Japan’s Self-Defense Forces say Chinese fighters repeatedly directed fire-control radar at Japanese F-15s shadowing the group near Okinawa, a step that can signal preparations to fire weapons. Tokyo summoned China’s ambassador Wu Jianghao to protest what it called a dangerous and regrettable act, while Beijing denied the radar targeting and accused Japanese aircraft of harassing normal training.
The incident lands on top of a broader 2025 China–Japan diplomatic crisis triggered by Prime Minister Sanae Takaichi’s explicit statement that a Chinese attack on Taiwan could constitute a survival-threatening situation for Japan, potentially justifying collective self-defense. Beijing has retaliated with travel advisories, frozen seafood import talks and a surge in military deployments across East Asian waters, while Japanese leaders, operating under a 2022 security strategy that labels China the “greatest strategic challenge,” promise to respond calmly but firmly and deepen coordination with the United States and Taiwan. The radar row highlights how tightly the East China Sea island dispute, Japan’s rearmament, and Taiwan’s security have become intertwined—and how an accident near Okinawa could drag multiple powers into a crisis.
Key Indicators
People Involved
Organizations Involved
The Government of Japan, led by Prime Minister Sanae Takaichi during the 2025 crisis, is responsible for setting and implementing the country’s increasingly assertive defense and foreign policy toward China and Taiwan.
The JSDF, including the Air Self-Defense Force (JASDF) and Maritime Self-Defense Force (JMSDF), is responsible for monitoring and responding to Chinese air and naval activity around Japan.
The PLA Navy operates China’s growing fleet of aircraft carriers, destroyers and coast guard escorts that routinely transit near Japanese territory and around Taiwan.
China’s foreign ministry manages diplomatic relations with Japan, issues travel advisories, and publicly responds to security statements by Tokyo and Washington.
USFJ oversees tens of thousands of U.S. military personnel and major bases in Okinawa and mainland Japan, making it the key ally whose forces would be drawn into any armed clash between China and Japan.
Timeline
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China responds to new U.S. security strategy, restates Taiwan red line
Public StatementThe Chinese government denounces the latest U.S. National Security Strategy, which calls for deterring conflict with Beijing and strengthening Indo‑Pacific military posture, and reiterates that Taiwan remains a core red line. Taiwan welcomes the U.S. stance and announces long-term defense spending increases, while Japan’s evolving policy and the Liaoning incident underscore how U.S., Chinese and Japanese strategies are colliding over Taiwan.
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Liaoning continues high-tempo air operations as China and Japan trade barbs
Military ActivityJapan confirms that Liaoning’s aircraft carried out around 100 total take‑offs and landings over December 6–7, including operations between Okinawa and Minamidaito and east of Kikai Island, even as the radar dispute unfolds. Tokyo reiterates that it will respond calmly but firmly, while Beijing rejects radar allegations and warns Japan against harassing its drills or meddling over Taiwan.
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Japan summons Chinese ambassador to protest radar incident
DiplomacyJapan’s foreign ministry summons Ambassador Wu Jianghao to lodge a formal protest over the radar lock incidents, calling them dangerous and unacceptable. China’s embassy denies that fire-control radar was used and instead accuses Japan of endangering flight safety by approaching too closely, demanding that Tokyo restrain its frontline forces.
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Liaoning carrier group transits near Okinawa into the Pacific
Military ActivityJapan’s defense ministry tracks the Liaoning and three missile destroyers as they pass between Okinawa’s main island and Miyako Island into the Pacific, then turn northeast between Okinawa and Minamidaito. Carrier aircraft conduct intensive training throughout, with no reported incursions into Japanese territorial waters or airspace but sustained presence in Japan’s vicinity.
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Japan accuses J-15s from Liaoning of locking fire-control radar on JASDF jets near Okinawa
IncidentJapan says that on December 6 Chinese J-15 fighters operating from the carrier Liaoning intermittently directed fire-control radar at JASDF F‑15s in two separate incidents over international waters southeast of Okinawa. Tokyo labels the actions dangerous and extremely regrettable and warns that radar illumination is tantamount to signaling a potential attack. China disputes the claims and accuses Japan of harassment.
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China rolls out retaliatory measures against Japan over Taiwan stance
Economic MeasureChina summons the Japanese ambassador in Beijing, issues a travel advisory against Japan, restricts cultural exchanges, and suspends steps toward resuming imports of Japanese seafood halted after the Fukushima water release. These measures are framed as responses to Takaichi’s Taiwan comments and add an economic dimension to the security crisis.
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Chinese consul in Osaka posts threatening message about Japan’s leader
IncidentChinese Consul General Xue Jian posts on X that there is no choice but to "cut off" the dirty neck that has lunged at China, widely understood as referring to Takaichi. Japan protests and demands disciplinary action; the post is later deleted, but Beijing does not publicly retract its substance. The rhetoric further poisons the atmosphere before the December radar incident.
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New Japanese PM Takaichi links Taiwan attack to Japan’s right of collective self-defense
Public StatementIn Diet deliberations, Prime Minister Sanae Takaichi states that a Chinese armed attack on Taiwan involving warships could constitute an existential crisis for Japan under its 2015 security legislation, legally enabling collective self‑defense. Chinese officials argue this challenges the One-China principle and interferes in China’s internal affairs, marking the start of a 2025 China–Japan diplomatic crisis.
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PLA launches multi-day drills and quasi-blockade around Taiwan
Military ActivityChina begins large-scale joint exercises around Taiwan, including rehearsal blockade and strike missions. The drills deploy dozens of aircraft and more than 20 naval and coast guard ships, including the Shandong carrier group, in positions that also threaten Japanese and U.S. interests in the broader region.
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Japan defense white paper again calls China the greatest strategic challenge
PolicyIn its 2024 defense white paper, Japan reiterates that China poses an unprecedented and greatest strategic challenge, citing repeated Chinese coast guard incursions near the Senkaku Islands and dangerous aerial maneuvers, including a JH‑7 bomber flying within about 30 meters of a Japanese surveillance plane over the East China Sea.
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Carrier Shandong drills near Okinawa and Taiwan during "United Sharp Sword"
Military ActivityChina’s second aircraft carrier, Shandong, participates in large-scale exercises that simulate air and sea strikes on Taiwan from waters close to Okinawa. Japan’s defense ministry reports around 120 carrier aircraft sorties in 48 hours and tracks the group as it sails into the western Pacific and later back to the South China Sea, foreshadowing Liaoning’s 2025 operations.
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Japan adopts new security strategy labeling China its greatest strategic challenge
PolicyJapan approves a revised National Security Strategy, National Defense Strategy, and Defense Buildup Program that collectively describe China as an unprecedented and greatest strategic challenge, commit to acquiring counterstrike capabilities, and aim to raise defense spending to around 2% of GDP within five years. Beijing denounces the move as a departure from pacifism.
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China declares East China Sea Air Defense Identification Zone
PolicyChina announces an ADIZ over much of the East China Sea, including airspace above the Senkaku/Diaoyu Islands and overlapping with existing Japanese and South Korean ADIZs. Japan, the U.S. and others criticize the move as destabilizing and continue flying military aircraft through the zone without complying with Chinese rules.
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Japan accuses Chinese frigate of locking weapons radar on JMSDF destroyer
IncidentJapan’s defense minister says a Chinese warship aimed fire-control radar at a JMSDF destroyer near the Senkaku Islands, and at a helicopter days earlier, calling it a very dangerous act. China denies using fire-control radar and accuses Tokyo of hyping the "China threat." The incident becomes an early template for later disputes about radar lock‑ons.
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Japan nationalizes three Senkaku Islands, angering Beijing
PolicyThe Japanese government purchases three privately owned Senkaku Islands—Uotsuri, Minami‑Kojima and Kita‑Kojima—for ¥2.05 billion, bringing them under state ownership. China condemns the move as theft of its territory and steps up patrols around the islets, deepening the dispute.
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Chinese fishing trawler collides with Japan Coast Guard near Senkaku Islands
IncidentA Chinese trawler collides with two Japan Coast Guard patrol vessels in disputed waters near the Senkaku/Diaoyu Islands. Japan detains the captain, triggering a major diplomatic row and setting the tone for a new era of tense maritime confrontations between China and Japan.
Scenarios
Managed Standoff: More Close Calls, No Shooting
Discussed by: Mainstream security analysts and think tanks such as CSIS, Brookings and Japanese defense white papers
In this scenario, China and Japan continue to engage in high‑tempo military operations around the Senkaku/Diaoyu area, Okinawa, and the approaches to Taiwan, including regular carrier deployments and JASDF scrambles. Radar illuminations, aggressive intercepts, and political barbs recur, but both sides avoid crossing the line into the actual use of force. Domestic political incentives in both countries favor toughness but not war, and U.S. diplomatic pressure quietly encourages restraint. Over time, this becomes the "new normal": risk remains high, but incidents are contained to protests, economic measures, and incremental military buildups rather than open conflict.
Crisis Management Architecture: Rules for Dangerous Skies and Seas
Discussed by: Specialists referencing the Japan–South Korea radar dispute settlement and existing Code for Unplanned Encounters at Sea
Faced with repeated near‑misses and growing concern from the United States and other regional actors, Beijing and Tokyo eventually create or revitalize military‑to‑military communication channels and technical protocols for encounters at sea and in the air. Drawing on how Japan and South Korea resolved their 2018 radar lock dispute in 2024 by agreeing on measures to prevent recurrence, China and Japan could adopt more detailed procedures for communications, distance thresholds, and the use of radar modes during interceptions. This would not resolve the underlying sovereignty disputes or Taiwan tensions, but would reduce the risk that future radar or collision incidents spiral out of control.
Accidental Shootdown or Collision Triggers Limited Armed Clash
Discussed by: Risk scenarios in defense commentary, including comparisons to past U.S.–China aerial incidents
In a worst‑case near‑term scenario, another close intercept in the crowded airspace near Okinawa leads to an accidental collision or a misinterpreted radar lock, resulting in the loss of a Chinese or Japanese aircraft—or both. Domestic pressure in either country could make it difficult to back down. Japan might invoke its security laws and request U.S. help, while China could respond with missile drills or limited strikes against non‑populated targets such as radar sites. Even if leaders in Beijing, Tokyo, and Washington want to avoid full‑scale war, a localized exchange of fire would represent a serious breach of the post‑1972 norm of no direct combat between Chinese and Japanese forces. The Hainan Island incident of 2001 shows that accidents can be contained, but also how politically fraught forced landings and detentions can be.
Taiwan Contingency Draws Japan Directly into Conflict with China
Discussed by: Longer-term assessments by Japanese strategists and U.S. Indo-Pacific planning documents
If China attempts to blockade or attack Taiwan at scale, the PLA would likely operate in or near Japanese airspace and waters, target U.S. bases in Okinawa, and contest sea lanes between Japan and the Bashi Channel. Under the 2015 security legislation and the interpretation articulated by Takaichi, Tokyo could deem this a survival‑threatening situation, enabling collective self‑defense in support of the United States and Taiwan. Japanese missile units might strike PLA staging areas or ships, while JASDF and JMSDF forces help defend U.S. assets and sea lanes. This scenario would transform current radar and carrier incidents from edge-of-crisis episodes into precursors to a major regional war. The scale of potential escalation and economic disruption makes this outcome widely feared but still considered a medium‑term possibility rather than an immediate likelihood.
Deepening Decoupling: Security Tensions Drive Economic and Social Separation
Discussed by: Asia policy and business analysts tracking tourism, trade and supply-chain shifts
Beyond the risk of kinetic conflict, a plausible trajectory is a gradual but deepening economic and social decoupling between China and Japan, catalyzed by security crises. Travel advisories, cuts to cultural exchanges, and targeted trade restrictions—such as China’s seafood import suspension—could become semi‑permanent features. Japanese firms accelerate diversification of supply chains away from China, while Chinese consumers and regulators increasingly treat Japan as politically hostile. Even if outright war is avoided, this scenario would reshape the economic foundation of the relationship and harden bloc politics in the Indo‑Pacific.
Historical Context
2010–2013 Senkaku Escalation and the First China–Japan Radar Lock Crisis
2010–2013What Happened
From 2010 to 2013, the Senkaku/Diaoyu Islands dispute moved from a relatively low‑level maritime issue to a central strategic flashpoint. The 2010 collision between a Chinese trawler and Japanese Coast Guard vessels led to the arrest of the Chinese captain and a major diplomatic spat. In 2012, Japan nationalized three of the islands by purchasing them from a private owner for ¥2.05 billion, prompting fierce Chinese protests and increased patrols. In early 2013, Japan accused Chinese frigates of locking fire-control radar on a JMSDF destroyer and helicopter near the islands, which China denied, calling Japan’s claims a smear. These events normalized a pattern of close encounters, protests, and dueling narratives that closely resembles today’s radar dispute.
Outcome
Short term: Despite intense rhetoric, neither side resorted to force. Diplomatic channels remained open, and both militaries adjusted to a higher operational tempo around the islands without formal rules of the road.
Long term: The crises entrenched domestic narratives of threat on both sides, set precedents for selective radar use and denial, and paved the way for later steps such as China’s East China Sea ADIZ and Japan’s 2022 shift toward counterstrike capabilities.
Why It's Relevant
The 2013 radar lock incidents show that both China and Japan have experience walking back from the brink after dangerous encounters, but also that denials and propaganda can leave underlying risks unresolved. The 2025 Liaoning radar dispute is unfolding along similar lines, with Tokyo emphasizing danger and Beijing rejecting the facts, suggesting that without new mechanisms, history may repeat rather than rhyme.
2018 Japan–South Korea Radar Lock Dispute and Its 2024 Resolution
2018–2024What Happened
In 2018, Japan and South Korea clashed over an incident in which Tokyo claimed a South Korean warship had locked fire-control radar on a JMSDF patrol aircraft, a charge Seoul disputed. The dispute badly strained bilateral defense ties and cooperation with the United States. After years of tension, the two governments agreed in June 2024 to normalize defense exchanges and adopted measures—such as adherence to the Code for Unplanned Encounters at Sea (CUES) and improved communications—to prevent recurrence, while effectively shelving the factual dispute.
Outcome
Short term: The 2018–2019 dispute led to mutual recriminations, suspended military exchanges, and complicated trilateral coordination with Washington.
Long term: By 2024, both sides recognized that leaving the issue unresolved endangered broader strategic cooperation. Their agreement to focus on practical prevention rather than assigning blame offers a template for managing technically complex, politically charged radar incidents.
Why It's Relevant
The Japan–South Korea case illustrates how radar lock controversies can fester for years but eventually be addressed through technical protocols and confidence‑building rather than public adjudication. While China–Japan relations are more adversarial than Japan–South Korea ties, the 2024 settlement shows that even entrenched narratives can give way to pragmatic risk‑reduction—an option that may become attractive if close calls around Okinawa keep multiplying.
2001 Hainan Island Incident: U.S.–China Aerial Collision and Diplomatic Climb-Down
April 2001What Happened
On April 1, 2001, a U.S. Navy EP‑3E signals intelligence aircraft and a Chinese J‑8 fighter collided in mid‑air over the South China Sea near Hainan Island. The J‑8 broke apart and its pilot was lost, while the severely damaged EP‑3 made an emergency landing on Hainan without China’s permission. Chinese authorities detained the 24 U.S. crew members for 11 days, and the incident sparked a heated war of words between Washington and Beijing. The standoff ended after the U.S. delivered a carefully worded letter expressing sorrow for the loss of the pilot and for the aircraft’s unauthorized landing, allowing both sides to save face.
Outcome
Short term: The crew was eventually released and the aircraft returned to U.S. custody after being disassembled, but the episode exposed how quickly routine surveillance flights can escalate into international crises.
Long term: The incident encouraged both countries to refine their intercept and surveillance practices, but close encounters and differing legal views on air and maritime operations have continued, resurfacing in later U.S.–China and now China–Japan tensions.
Why It's Relevant
The Hainan incident underscores the dangers of high‑risk intercepts and the importance of crisis communication and face‑saving diplomacy. While the U.S. and China ultimately de‑escalated, the political costs were high on both sides. For Japan and China, which have their own wartime history and domestic sensitivities, managing a similar forced landing or shootdown near Okinawa could be even harder, making preventive rules and hotlines particularly valuable.