Introduction

Over the past decade, the Senkaku Islands have emerged as a significant flashpoint in Japan-China relations. The islands have been peacefully under Japanese sovereignty since 1895,when these islands were incorporated into Japan. After World War II, they were temporarily under the US administration as part of Okinawa and then returned to the Japanese administration in 1972.(*1) Recently, the islands have become crucial to regional security due to their strategic location, potential hydrocarbon reserves, and symbolic significance in nationalist narratives in East Asia.

In 2012, the Japanese government transferred the ownership of the three islands from private owners to the government. This transfer provoked strong reactions from China. By developing the world's largest coast guard and establishing the 2021 Coast Guard Law, the Chinese government has created a mechanism for maintaining a persistent presence in disputed waters while avoiding the escalatory risks associated with naval deployments. This transformation exemplifies China's broader "gray zone" strategy—employing coercive actions below the threshold of armed attack to alter the status quo gradually.(*2) The paper analyzes how this approach has prompted specific countermeasures from Japan and its international partners, with implications for crisis management and regional security architecture.

Historical Context and Institutional Evolution

Prior to 2013, China's maritime law enforcement capabilities were fragmented across five separate agencies—China Marine Surveillance, Maritime Safety Administration, Fisheries Law Enforcement Command, China Customs, and Maritime Border Police—each with distinct jurisdictions, command structures, and priorities, leading to inefficiencies and coordination issues. The fragmentation of operations regarding the Senkaku Islands had become issues due to ineffectiveness after Japan transferred ownership of the three islands out of five in 2012, such as CMS vessels patrolling while FLEC escorted fishing boats.(*3)

The lack of coordination among agencies resulted in competing assertions of Chinese claims and inconsistent messaging. In March 2013, the Chinese government restructured its maritime agencies, merging four out of five law enforcement bodies into the China Coast Guard (CCG) under the State Oceanic Administration. This change aimed to reduce inefficiencies and competition among agencies and improve maritime law enforcement and rights protection.(*4)

The CCG's institutional evolution continued in 2018 when it was transferred from civilian control to the People's Armed Police under the Central Military Commission, fundamentally shifting its status from civilian law enforcement to a paramilitary organization with direct military command integration. This transformation culminated in the 2021 Coast Guard Law, which explicitly authorizes the use of force against foreign vessels within the waters under China’s jurisdiction and creates a legal framework for potentially escalatory behavior.(*5)

Capability Transformation and Operational Impact

A dramatic expansion in its capabilities has accompanied the CCG's institutional consolidation. From approximately 51 large ocean-going cutters in 2012, the fleet expanded to 159 vessels by 2023, more than double the number of Japanese Coast Guard assets.(*6) This growth includes commissioning 12,000-ton class vessels—larger than many naval destroyers—equipped with 76mm cannons and helicopter facilities, effectively blurring traditional distinctions between Coast Guard and naval assets.

This capability transformation has directly impacted operations around the Senkaku Islands. The pre-2013 pattern of occasional, sporadic intrusions has been replaced by near-continuous presence in the contiguous zone and increasingly frequent intrusions into the territorial waters. Japan Coast Guard data indicates a significant increase in the presence in the Japanese contiguous zones as well as the frequency and duration of these intrusions into the territorial sea by harassing Japanese fishery fleets,(*7) fundamentally altering the decades-old status quo.

Although the actual force has not yet been used in confrontations near the Senkakus, the armed CCG's expanded presence has elevated escalation risks through three mechanisms: increased opportunities for unplanned encounters in the waters, military command integration complicating crisis management channels, and the Coast Guard Law's explicit authorization of force under broadly defined circumstances.

Japan's Responsive Measures

Japan has implemented a multi-faceted response to China's Coast Guard transformation, evolving from reactive measures in 2012-2015 to a more comprehensive strategy since 2016. Key components include:

1. Capacity Enhancement: Japan has systematically expanded its Coast Guard capabilities through annual budget increases, establishing the fleets dedicated to Senkaku Guard and Security operations in February 2016.(*8) The annual Ministerial Meeting to enhance the capability of JCG has been held since 2016, aiming at the institutional development of JCG by the whole government.(*9)
2. Alliance Adaptation: Japan-U.S. Security consultations have continuously confirmed the application of Article V of the Treaty of Mutual Cooperation And Security Between Japan and the United States of America and increasingly emphasized coast guard cooperation, resulting in joint exercises, intelligence sharing protocols, and coordinated response mechanisms tailored to 'gray zone' scenarios.(*10)
3. Enhanced JCG-JSDF Cooperation: In 2015, the Cabinet decided that in case a foreign warship did not exercise the right of innocent passage within the Jpaan’s territorial sea, an accelerated procedure would be used to mobilize the JSDF assets under the Maritime Security Operation.(*11) In addition, the Control Guideline of JCG by the Minister of Defense was adopted in April 2023, enabling further cooperation between JCG and JSDF in case of an armed attack against Japan.(*12)

These measures collectively demonstrate Japan's recognition that effective countermeasures must be able to counter China's approach in spanning institutional, legal, operational, and diplomatic domains.

Conclusion

China's Coast Guard transformation has fundamentally altered security dynamics around the Senkaku Islands. The 2013 consolidation and 2018 military integration created an instrument that effectively blurs the line between law enforcement and military operations, enabling China to maintain a continuous presence in waters around the Islands while avoiding the immediate escalation risks associated with naval deployments.

For Japan, this "gray zone" challenge has necessitated adaptations across multiple domains, from enhancing the JCG's capabilities to alliance management to further cooperation with JSDF. Japan has developed crisis management mechanisms, as the CCG's regular operations create continuous tensions that complicate regional security dynamics.

The CCG institutional transformation demonstrates China's strategic preference for incremental approaches to territorial disputes and illustrates how administrative reforms can yield strategic advantages by creating new operational realities. As similar patterns emerge across the Indo-Pacific, Coast Guards have become frontline instruments in regional competition, challenging traditional assumptions about escalation management and maritime security. Understanding these dynamics remains essential for preventing inadvertent escalation in contested waters throughout the region.

Notes

1. Ministry of Foreign Affairs Japan, “Situation of the Senkaku Islands,” https://www.mofa.go.jp/a_o/c_m1/senkaku/page1we_000010.html.
2. Erickson, Andrew S.; Hickey, Joshua; and Holst, Henry (2019) "Surging Second Sea Force: China’s Maritime Law-Enforcement Forces, Capabilities, and Future in the Gray Zone and Beyond," Naval War College Review, 72(2). https://digital-commons.usnwc.edu/nwc-review/vol72/iss2/4.
3. International Crisis Group, "Dangerous Waters: China-Japan Relations on the Rocks," Asia Report, No. 245 (April 8, 2013): 12-15, https://www.crisisgroup.org/asia/north-east-asia/china/dangerous-waters-china-japan-relations-rocks.
4. Lyle J. Morris, “Militarizing Coast Guard operations in the maritime gray zone,” in China’s Maritime Gray Zone Operations, eds. Andrew S. Erickson and Ryan D. Martinson. Annapolis, MD: Naval Institute Press, 2019, pp. 77-91.
5. Kentaro Furuya, “The China Coast Guard Law and Challenges to the International Order — Implications for CCG Activity around the Senkaku Islands,” International Information Network Analysis, March 8, 2021, https://www.spf.org/iina/en/articles/furuya_03.html.
6. Japan Coast Guard, “海上保安レポート (Coast Guard Annual Report) 2024,” May 2024, https://www.kaiho.mlit.go.jp/info/books/report2024/html/honpen/3_03_chap2.html.
7. ibid.
8. Japan Coast Guard, “海上保安レポート(Coast Guard Annual Report) 2016,” May 2016, https://www.kaiho.mlit.go.jp/info/books/report2016/html/topics/topics16_02.html.
9. Prime Minister of Japan and His Cabinet, “海上保安能力強化に関する関係閣僚会議 (the Ministerial Conference to enhance the capability of the Japan Coast Guard),” https://www.kantei.go.jp/jp/singi/kaihotaisei/index.html.
10. For example, the US Department of Defense, “Joint Statement of the Security Consultative Committee ("2+2"), ” July 28, 2024, https://www.defense.gov/serve-from-netstorage/News/Releases/Release/Article/3852169/joint-statement-of-the-security-consultative-committee-22/index.html.
11. Cabinet Decision, “我が国の領海及び内水で国際法上の無害通航に該当しない航行を行う外国軍艦への対処について (the measures against a warship not exercising the right of innocent passage within the Japan’s territorial waters),” May 14, 2015, https://www.cas.go.jp/jp/gaiyou/jimu/pdf/gaikokugunkantaisho.pdf.
12. In detail, Kentaro Furuya, “The Significance of and Issues Regarding the Formulation of the Japan Coast Guard Control Guideline,” Aug. 18, 2023, International Information Network Analysis, https://www.spf.org/iina/en/articles/furuya_04.html.

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