This article is part of Conceptualization of “Maritime Security” in Southeast Asia, a series of analyses produced by experts convened by the S. Rajaratnam School of International Studies.
“Maritime security” Japan’s national language.
“海洋安全保障 (Kaiyo anzen hosho)” is the most commonly used phrase for maritime security in Japanese. The phrase consists of three words. The first word, “kaiyo,” means maritime or ocean. “Anzen” stands for safety in general. “Hosho” means to ensure or to secure.
“海上警備 (kaijou keibi)” is another translation for “maritime security.” However, its meaning quite specific. Kaijou keibi refers to security activities by the Japan Coast Guard (JCG) to maintain good order at coastal zones next to venues of an important event, such as a summit meeting or the Tokyo Olympics. When 行動(koudou), meaning operation in English, is added the resulting 海上警備行動 (kaijou keibi kodou) means Maritime Security Operation. This has a very specific meaning for the Japan Self-Defense Force (JSDF). Article 82 of the Japan Self-Defense Act stipulates “when especially necessary to protect life or property or maintain public order at sea, the Minister of Defense may, with the approval of the Prime Minister, order Self-Defense Forces units to undertake the necessary operations at sea.”  Under this Article, “especially necessary” is construed as a situation that requires capabilities beyond those of the Japan Coast Guard (JCG). The geographical area of the operation is not restricted to Japan’s territorial seas but includes its EEZ and the high seas. The Japanese government has been very cautious regarding the invocation of this Article, invoking it only three times. 
“領海警備 (Ryokai keibi)” is a related term that means security operations within territorial and internal waters. An example of ryokai keibi is operations around the Senkaku Islands. They are carried out to protect sovereignty from activities by foreign activities harmful to Japan’s peace, good order, and safety.
Japan’s definition and usage of “maritime security”
There seems to be no official definition of maritime security in Japan. However, the words repeatedly appear in official documents.
Japan’s key documents for defining and understanding maritime security
Official Japanese documents tend to identify threats and describe the approved strategy to counter those threats. The Basic Plan on Ocean Policy, the National Defense Program Guidelines, and Defense White Paper are important to understand Japan’s approach to maritime security.
The Basic Plan on Ocean Policy sets out, inter alia, Japan’s comprehensive maritime security policy. The current Basic Plan states the three main policy directions for maritime security. These are to secure 1) national interests in Japan’s territorial waters, etc., 2) stable use of Japan’s important sea lines of communication (SLOCs), and 3) to strengthen the international maritime order to ensure freedom of use of the oceans. 
The National Defense Program Guidelines (NDPG) also touch upon maritime security. The NDPG for the fiscal year 2019 and beyond formulate a maritime security strategy to “ensure the safety of maritime and air traffic by strengthening the order of “Open and Stable Oceans,” an order based on fundamental norms such as the rule of law and freedom of navigation.” The Guidelines explain that, because Japan is an island nation, it heavily depends on energy and food imports and maritime security is essential to its peace and prosperity.
The Guidelines also discuss gray zone situations as a significant security threat, especially at sea. Gray zone situations are defined as “neither pure peacetime nor contingencies over territory, sovereignty, and maritime economic interests.” Typical examples are the regular intrusions of Chinese Coast Guard ships into the territorial waters of the Senkaku Islands and the possible landing on the Senkaku Islands by Chinese maritime militia forces disguised as fishermen or civilian protestors.
The 2021 Defense White Paper recognizes unilateral activities not based on the existing international law, including the UN Law of the Sea Convention in the South China Sea, as maritime security threats in the vital Japanese SLOCs. It specifically points to maritime threats such as attacks against tankers sailing around Yemen, the Bab-el-Mandeb Strait, and the Hormuz Strait; piracy off the coast of Somalia and in Asia; and military activities in the Arctic Sea.
Elements of Japan’s approach to maritime security. Environmental protection, mariner safety, fisheries management, resource management (other than fisheries), counter-terrorism, law enforcement, naval operations, deterrence?
All of these are recognized as maritime security threats in the Basic Plan Phase III. Particularly, the Basic Plan Phase III developed the concept of “comprehensive maritime security” and identified the threats and strategies against these threats. Because these threats listed in the questions are mentioned in the Plan, they should all be considered matters of maritime security.
Evolution in Japan’s usage of the term “maritime security”
As perceived threats have evolved, the definition of maritime security has changed. As globalization proceeded substantially after the Cold War, maritime security extended to include non-traditional security threats, such as transnational organized crimes and terrorist attacks. In order to counter the threats of terrorist attacks, SOLAS XI-2 regarding maritime security was adopted in 2002. A new domestic law was enacted for the implementation of the new regulations within Japan.
In areas surrounding Japan, gray zone situations have been increasingly recognized as a severe threat. China’s continuous presence in Japan’s contiguous zones and occasional intrusion in the territorial sea surround Senkaku Islands deteriorated the security environment in Southwest Japan. In particular, the situation worsened in 2010 after the apprehension of a Chinese fishing boat involved in collisions with JCG patrol ships and in 2012 after the ownership of the islands was transferred to the Japanese government. A swarm of up to 300 Chinese fishing boats appeared in the Senkaku Islands in 2016 and intrusion by Chinese Coast Guard ships and fishing vessels into Japanese territorial seas occurred at record-breaking rates. Recently, the Chinese Coast Guard started harassing Japanese fishery fleets in the territorial sea. JCG ships must counter these threats as a part of Japan’s comprehensive maritime security strategy.
Different maritime threats appeared in the vital Japanese SLOCs, too. The number of piracy and armed robbery cases in Asia surged in 2000 and off Somalia in 2008. Provocative activities by Chinese authorities in the South China Sea became a concern for freedom of navigation and international trade. Tanker ships owned or operated by Japanese companies were attacked in the Hormuz Strait in 2019 and 2021. These incidents are threats to freedom of navigation and international trade, threatening Japan’s resource supply.
Additional context for Japan
Amid the threats identified in the above documents, the most significant maritime threat is the activity by the Chinese Coast Guard around the Senkaku Islands. This issue is not just a violation of international law but a threat to the shared values of the existing international order. U.S. administrations have continuously stated that Article V of the Japan-U.S. Security Alliance applies to the Senkaku issue; however, the Chinese activities have never been suspended, and have even intensified.
Similarly, the U.S. presence in the South China Sea is an important issue. China still claims historical rights in almost the entire region of the South China Sea, which was denied by the Arbitral Tribunal in 2016. China intends to enhance its control over the South China Sea in contradiction to the existing legal order. The presence of the U.S. Navy is essential to maintain freedom of navigation and the rule-based order in this region.
 Article 82 of the Japan SelfDefense Forces Act (Law No. 165 of 1954, as amended)
 Special Committee concerning the Guidance for Japan-US Defense Cooperation, 145th House of Representatives (March 31, 1999) (testimony of Hiromu Nonaka, Chief Cabinet Secretary), No. 4.
 National Security Committee, 154th House of Representatives (April 4, 2002) (testimony of Gen Nakatani, Minister of Defense), No. 5
More in detail information of the Maritime Security Operations by the Japan Self-Defense Force, Furuya, Kentaro, “Maritime Security—The Architecture of Japan’s Maritime-Security System in the East China Sea,” Naval War College Review, Vol. 72, No. 4, 2019.
 Japan Coast Guard, The Japan Coast Guard White Paper, 2012, Sep. 2012. https://www.kaiho.mlit.go.jp/info/books/h12haku/2bu1-1.htm.
 The Basic Plan on Ocean Policy was formulated by virtue of Article 16 of the Basic Act on Ocean Policy (Act No. 33 of April 27, 2007), https://www8.cao.go.jp/ocean/english/act/pdf/law_e.pdf.
 Provisional translation is available. Cabinet Office. The Basic Plan on Ocean Policy Phase III, May 2018, https://www8.cao.go.jp/ocean/english/plan/pdf/plan03_e.pdf.
 Ministry of Defense. National Defense Program Guidelines for Fiscal Year 2019 and Beyond, December 2018, pp. 6-7. https://www.mod.go.jp/j/approach/agenda/guideline/pdf/20181218_e.pdf.
 Ministry of Defense. Defense of Japan, 2021. P.42. https://www.mod.go.jp/en/publ/w_paper/wp2021/DOJ2021_EN_Full.pdf.
 “ibid. P.161-162, p.190.
 Ministry of Foreign Affairs. Status of activities by Chinese government vessels and Chinese fishing vessels in waters surrounding the Senkaku Islands, 2016, https://www.mofa.go.jp/files/000180283.pdf.
 “Gulf of Oman tanker attacks: What we know,” BBC, June 18, 2019. https://www.bbc.com/news/world-middle-east-48627014; Ministry of Foreign Affairs. Press Conference by Foreign Minister Taro Kono, June 14, 2019. https://www.mofa.go.jp/press/kaiken/kaiken4e_000654.html.
 Ministry of Foreign Affairs. Attack on a ship in the Arabian Sea off the coast of Oman (Statement by Press Secretary YOSHIDA Tomoyuki), August 2, 2021. https://www.mofa.go.jp/press/release/press3e_000222.html.