Replicating its well-known salami-slicing tactic, China is steadily expanding its military activities around the disputed islands located in the East China Sea between Japan and China, escalating the level of military tensions on sea border.
Most recently, the Joint Staff Office of the Japanese Defense Ministry announced on May 25 that the Liaoning aircraft carrier of China’s People’s Liberation Army Navy (PLAN) sailed in the East China Sea off the coast of the Senkaku Islands in Okinawa Prefecture, along with two Type 052D Luyang III-class destroyers – dubbed the “Chinese Aegis” – and two Type 054A Jiangkai II–class guided-missile frigates.
The islands, which are known as the Diaoyu in China, are administered by Japan but claimed by China and Taiwan.
On May 27, the JSO said that the Japan Maritime Self-Defense Force (JMSDF) has confirmed that fighter jets and helicopters aboard the Liaoning had conducted a total of about 120 takeoffs and landings in and around the sea area about 240 km north of Kubajima in the Senkaku Islands between May 25 and 26.
In response, two Japan Air Self-Defense Force fighter jets scrambled from the Naha Air Base in Okinawa’s main island.
Chinese aircraft carriers have conducted takeoff and landing operations involving fighter jets in the wider East China Sea in the past, but this is the first time the Japanese Defense Ministry has issued an announcement about such operations.
A spokesperson at the JSO told The Diplomat on May 30 that the administrative agency publicized the incident because this was an unusual case that required close attention.
In particular, the spokesperson said the Chinese activities took place on the Japanese side of the China-Japan median line and within Japan’s exclusive economic zone (EEZ) – closer to the Senkaku Islands than ever before.
On May 27, the Chinese fleet kept sailing southeast through the Miyako Strait, the waters between the main island of Okinawa and Miyako Island, heading toward the Pacific Ocean. On the same day, fighter jets and helicopters from the Liaoning also took off and landed in the waters about 190 km southeast of Miyako Island.
The following day, Taiwan’s Defense Ministry said it is on high alert for the Liaoning sailing in waters southeast of Taiwan. It said nine PLAN ships, including the aircraft carrier and a Chinese government vessel, as well as 31 sorties of fighter jets, drones and other aircraft were spotted around Taiwan in the 24 hours up to 6 a.m. on May 28.
It is not clear whether the Chinese fleet was accompanied by a submarine, but it wouldn’t be strange if so. After all, the fleet appears to be the movement of an aircraft carrier strike group. It could be interpreted either as a simple exercise or as a rehearsal for a contingency centered on either the Senkaku Islands or Taiwan.
The distance between the Senkaku Islands and Naha Air Base is about 400 kilometers. This is almost the same distance between the Senkakus and Fuzhou Air Base in China’s Fujian Province.
In other words, by sending an aircraft carrier to waters about 200 kilometers from the Senkaku Islands, the Chinese military can enjoy a de facto air base closer to the disputed islands than any of Japan’s bases.
The Chinese Foreign Ministry on May 28 urged Japan to view activities by Chinese naval vessels “from an objective and reasonable perspective.”
“What I can tell you is that China’s military vessels’ activities in relevant waters are fully consistent with international law and international practice. We hope Japan will view this from an objective and reasonable perspective,” Chinese Foreign Ministry Spokesperson Mao Ning said at the regular press conference that day.
Meanwhile, on May 11, the Japan Coast Guard confirmed that a Chinese marine research vessel was extending a pipe-like object into the sea around the Senkaku Islands, within the Japanese EEZ, about 236 km north-northeast of Taisho Island in the Senkaku Islands. It was also on the Japanese side of the China-Japan median line.
Furthermore, on May 3, a helicopter took off from a China Coast Guard vessel that entered the territorial waters around Minamikojima Island in the Senkaku Islands, violating Japanese airspace.
Behind this Chinese activities is the dispute over the sovereignty of the Senkaku Islands, as well as conflicting views of the two countries on where the demarcation line should be placed between the EEZs of the two sides. China and Japan have been at loggerheads over the boundary. While Tokyo defines it as the line marking an equal distance from the coasts of the two countries, Beijing claims its EEZ extends to the edge of the continental shelf.
Legally, the United Nations Convention on the Law of the Sea (UNCLOS) allows coastal countries to regulate catch and seabed resources in an economic zone extending 200 nautical miles, or 370 km, from their shores. But when two coastal states’ EEZ intersect each other, the states must negotiate the boundary. Beijing and Tokyo, both of which ratified the convention in 1996, have not agreed on where the EEZ border lies.
In any case, China, which is strengthening its maritime expansion, is seeing the current state of Japanese public opinion, which shows little sense of crisis, and is employing its salami-slicing tactic to slowly change the situation by taking tiny steps to assert its presence.
In 2024, Admiral John Aquilino, then the commander of the United States Indo-Pacific Command, said that China has a “boiling frog” strategy. This strategy involves gradually increasing the military temperature so that the threat is underestimated until it is too late.
However, Admiral Samuel Paparo, the current commander of the U.S. Indo-Pacific Command, pointed out in a speech on May 2 that the PLA has significantly escalated its activities. “You hear the metaphor ‘boiling the frog’ … It’s a rapid boil,” he pointed out.
Japan must step up its response level to avoid becoming a “boiled frog” that does not notice changes or crises.