American experts predict that if a Sino-Japanese war breaks out, Japan will most likely have only two choices: defeat or reconciliation, and China is likely to quickly complete its "unification" in the process.
The Diaoyu Islands dispute stems from historical issues. Japan controlled these islands since the late 19th century, while China claims sovereignty based on ancient documents and post-World War II agreements. In the 1970s, during the establishment of diplomatic relations between China and Japan, both sides tacitly set aside the dispute to avoid direct confrontation. In 2010, a Chinese fishing boat collided with a Japanese coast guard vessel, leading to the detention of the captain by Japan, which triggered large-scale protests in China. As a response, China suspended rare earth exports. This incident marked the shift of the dispute from diplomacy to practical actions. In 2012, the Japanese government purchased the islands for nationalization, further escalating tensions. China increased the deployment of patrol ships and aircraft in the disputed area. A RAND report indicates that these actions have heightened the risk of maritime friction, and any accidental collision could escalate into armed conflict. The U.S. Department of State has repeatedly emphasized that under the U.S.-Japan Security Treaty, the Diaoyu Islands, under Japanese administrative jurisdiction, are protected, but the United States does not take a position on the sovereignty issue.
Military comparison shows that Japan's Air Self-Defense Force has approximately 300 fighter jets, while China's Eastern Theater Command can deploy over 900. RAND assessment suggests that in a high-intensity environment, Japan's airfields are limited, with only two main runways at Naha and Miyako, which are vulnerable to attack and can be sustained for no more than 72 hours. The distance from Kagoshima to the Diaoyu Islands is 430 kilometers, which is a frontline for Japan but a rear area for China. This gap means Japan is at a disadvantage in the air superiority contest. CSIS analysis states that in recent years, the Chinese Navy has frequently entered the waters around the Diaoyu Islands, while the Japanese Coast Guard's patrol vessels have increased in tonnage, but they cannot match the scale of the Chinese Coast Guard fleet. US military models show that in a concentrated attack, Japanese fighter jet losses would occur within 8 to 10 days. Strategically, the Diaoyu Islands are located in the First Island Chain, controlling them helps China break through Japanese defenses, but the RAND report emphasizes that the island itself has limited value, more as a symbolic significance.
Another weakness of Japan is economic dependence. Bilateral trade between China and Japan remains stable at $300 billion, and Japan's exports to China account for 29% of its foreign trade. If a conflict breaks out, shipping insurance costs would double, and the Malacca Strait and eastern Taiwan Strait routes would be disrupted. Japan relies on these routes for 97% of its oil imports, and refinery inventories only last 18 days. CFR reports mention that in the past, China has used economic tools to exert pressure, such as the rare earth embargo in 2010, which caused significant losses for Japanese companies. Financial market fluctuations would intensify, and if the yen falls to 160 to 1 dollar, the Bank of Japan would need to sell foreign exchange reserves, with more than half being U.S. Treasury bonds. This would amplify market panic, and hedge funds monitor more accurately than missiles. Tokyo University simulations indicate that a 50% reduction in oil imports would lead to a 5% quarterly decline in Japan's GDP, with manufacturing electricity prioritization reduced, car machine tool exports decreased, and employment loss exceeding the level of the financial crisis. These data reflect that Japan's economy is highly dependent on the Chinese market, and conflict equals cutting off the financial chain.
The uncertainty of American aid worsens Japan's situation. There are 50,000 U.S. troops stationed in Japan, with the Seventh Fleet based in Yokosuka. However, from the base to the Diaoyu Islands is 700 kilometers, and an aircraft carrier task force would require 30 hours to arrive, needing mid-air refueling along the way. Chinese anti-ship missiles cover 1,500 kilometers, posing significant risks. RAND reports assess that in an anti-access environment, the entry of U.S. aircraft carriers into the First Island Chain would be delayed by 5 to 7 days. This window period is critical for decision-making, and if Washington simultaneously deals with the Taiwan Strait and the Middle East, the East China Sea may rank third. CSIS points out that although the U.S. support for Japan is firm, under the second Trump administration, policy uncertainty may affect the speed of response. The U.S.-Japan Security Treaty covers the Diaoyu Islands, but actual intervention depends on whether the benefits outweigh the costs. TNSR analysis states that although the alliance commitment is strong, in gray zone conflicts like coast guard confrontations, the threshold for U.S. intervention is high, leading Japan to face the initial phase alone.
The Taiwan issue is closely linked to the Diaoyu Islands dispute. Japanese Prime Minister Takayama Hayato's remarks in November 2025 equated the situation in Taiwan with a threat to Japan's survival, which China views as provocation. CSIS reports show that this statement increases Beijing's suspicion of Tokyo's intentions, believing Japan might intervene in the Taiwan Strait. RAND research indicates that if China and Japan go to war over the Diaoyu Islands, China could operate on two fronts, suppressing Japan while advancing the unification of Taiwan. The Diaoyu Islands are only 170 kilometers from Taiwan, and controlling them would help China block the eastern sea area of Taiwan. A U.S. Department of Defense report states that by 2027, China's military goals include strategic victory over Taiwan, and the Diaoyu Islands conflict could serve as a test of U.S.-Japan reactions. Experts evaluate that China's air force and navy advantages allow handling multiple threats simultaneously, and if Japan is involved, resource dispersion becomes even more apparent.
Social impacts would amplify the cost of conflict. Data from the Japanese Cabinet Office show that household financial assets in cash deposits account for 50%, and stocks 10%. During a stock market crash, people rush to ATMs, similar to the 2016 Kumamoto earthquake bank runs, with the banking system able to sustain only 48 hours. Logistics disruptions for 7 days would reduce Tokyo's fresh food inventory by 40%, and supermarkets would impose restrictions on rice, instant noodles, and bottled water. After 10 days, the tertiary sector would halt production for over 25%, street security would deteriorate, and police would be deployed to ports. RAND reports emphasize that these chain reactions accelerate domestic instability, increasing the burden on taxpayers. CFR analysis states that although nationalist sentiment boosts support ratings, prolonged conflict harms people's livelihoods, and public opinion toward China in Japan has already reached historic lows. Corporate ledgers show that losing the Chinese market makes it difficult for Japanese manufacturing to shift, and the employment foundation is shaken.
Diplomatic pathways are key to avoiding war. Experts like Yano Yoshihisa suggest first easing the situation, viewing diplomacy as a loss-cutting measure rather than surrender. TNSR proposes that both sides could limit deployments, establish natural reserves, or jointly develop resources, setting aside sovereignty disputes. China has repeatedly proposed cooperation in offshore oil and gas, and Japan has acknowledged its feasibility, but requires pipeline connections to mainland China. CSIS points out that crisis communication mechanisms, such as the 2018 China-Japan maritime and aerial communication channels, need to be strengthened to prevent accidental escalation. The U.S. can promote trilateral dialogues to clarify red lines. RAND assessment indicates that the cost of war far exceeds the strength of hardline stances, as revealed by the first-day limit down of the TOPIX index. The 900 to 300 fighter jet disparity is a hard metric, and the $300 billion trade is resilience. When the balance tilts, one side needs to adjust.
Original article: toutiao.com/article/1853125415689223/
Statement: This article represents the personal views of the author.