This June could be remembered in the near future as a turning point when China intensified its unilateral attempt to challenge the status quo by using force and coercion in the East China Sea. Compared with China’s “usual” practice of navigating in the contiguous zone and intruding into Japanese territorial waters, there were two significant changes in both quantity and quality: the frequency of the intrusion and the apparent arms of ships.

Since June 20, China Coast Guard vessels have intruded into Japanese territorial waters 5 days in a row despite the warnings from the Japanese Coast Guard (JCG). This is an unprecedented pace; previously, China Coast Guard vessels had entered the Japanese territorial waters at most twice a month, and the intrusion had not lasted for longer than 3 days.

Moreover, these vessels were not “usual”. Since December 22 last year, the China Coast Guard has sent ships into the contiguous zone almost every day for more than 188 consecutive days. This is the longest such period since 2012, when the Japanese government acquired ownership of some of the Senkaku Islands from a Japanese owner. This “usual” entry had been carried out by three to four ships, of which at most one ship had equipped with a cannon. However, on June 7, the JCG headquarters said that each ship looked like it had a cannon. Since then, the number of armed ships has increased to more than two, at most all four of them. The armament continues when they intrude into the Japanese territorial waters. The attempts of China Coast Guard seem to be getting aggressive.

While the intent of having such apparent arms needs to be carefully assessed, it could be clearer in light of the recent trend of the China Coast Guard activating the Automatic Identification System (AIS). Normally, Japan Coast Guard vessels turn off the AIS to keep their capabilities and operations secret, and so did the China Coast Guard before. However, since 2023, China Coast Guard vessels have frequently begun to turn on AIS when approaching the contiguous zone and intruding into the Japanese territorial waters near the Senkaku Islands. This is similar to the situation in the South China Sea, where China is attempting to strengthen its “effective control”. Several experts point out that China is using AIS to demonstrate its presence both domestically and internationally. According to Dr. Mouri, "(L)ooking at the AIS information alone, the situation seems to be that there are only Chinese ships in the area. It gives the impression that China is gaining control of these waters. I think China hopes that this will have the effect of actively promoting its presence to the international community,"[1] she noted. The East China Sea in June was no exception. Records show that the AIS of China Coast guard vessels started to be activated around the Senkaku Islands.

In that South China Sea, China has claimed the territorial rights to islands and undersea resources by surrounding the almost the entire area with the so-called "nine-dash line" and has attempted to strengthen its effective control over the disputed maritime waters and reefs by building structures or by reclaiming and establishing bases. These unilateral claims have overlapped and therefore conflicted with coastal countries such as Vietnam, Malaysia, Brunei, Indonesia and the Philippines. Especially from 2023, the tension between China and the Philippines have frequently turned into physical collision over the Second Thomas Reef. It was reported that on June 17, a Philippine military supply ship collided with a China Coast Guard ships in the waters of the Second Thomas Reef. The Philippines and China are accusing each other of having clashed. In response to the collision, the Japanese government expressed serious concern over "repeated actions which obstruct freedom of navigation and increase regional tensions including recent dangerous actions that resulted in damage to the Filipino vessel and injuries to Filipinos onboard", and stated that it "opposes any unilateral attempts to change the status quo by force as well as any actions that increase tensions in the South China Sea" by reiterating the Joint Vision Statement issued at the Japan-US-Philippines Summit in April.

In June, there were China Coast Guard vessels entering the contiguous zone and intruding into Japanese territory at a significant rate, more equipped with a cannon. Given China’s attempts combine “effective control” with force and coercion in the South China Sea, these changes in the East China Sea should be seen in a broader context with the activation of AIS and other legal changes as well. Indeed, on June 15, a new China Coast Guard regulation went into effect that allows it to detain foreigners suspected of trespassing in China's claimed territorial waters for up to 60 days. This could lead to arbitrary detentions in “territories” claimed by China. This series of developments, in combination with public, legal, and coercive measures, indicates that China is intensifying its unilateral changes to the status quo. It is necessary to be cautious about whether China might start the “next slice” of salami also in the East China Sea.

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¹ NHK (2023), “Why Did China Coast Guard Vessels Change Intrusion into Territorial Waters Around Senkaku Islands in Okinawa?”, Available at https://www3.nhk.or.jp/news/ special/international_news_ navi/articles/feature/2023/06/ 02/32061.html (Accessed June 28, 2024). Translated by author.

[Statistical Data as of June 28]

Japan Coast Guard (JCG) daily updates the statistical data on the number of China Coast Guard vessels entering in the contiguous zone around the Senkaku Islands and intruding into Japanese territorial waters. The below is from the website of JCG.

(https://www.kaiho.mlit.go.jp/mission/senkaku/senkaku.html)

June	Contiguous zone	Territorial sea	June	Contiguous zone	Territorial sea
1	4		16	4
2	4		17	4
3	3		18	4
4	3		19	4
5	4		20	4	3
6	4		21	4	3
7	8	4	22	4	3
8	4		23	4	2
9	4		24	4	2
10	4		25	4
11	4		26	2
12	4		27	4
13	4
14	4
15	4

by Yu AKIMOTO
Researcher, Research Institute for Peace and Security

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