Tetsuo Kotani

China’s “Nine Gates” and Security Policy in the Indo-Pacific
Challenges for Japan*
Tetsuo Kotani**
Abstract
China has been conducting forays through nine straits into the Indian and Pacific Oceans.
It is imperative for China to secure free use of these routes and gain the ability to preventrival powers from using them. Of the nine straits that China is aiming to use, five lie
within Japanese territorial waters, and the Self-Defense Forces are constantly carrying out
monitoring and surveillance in these areas. The remaining four straits lie in the territorial
waters of other nations, and since Chinaʼs anti-access/area-denial (A2/AD) capabilities
are improving rapidly, keeping all nine straits constantly under surveillance, and closing
them in the event of a contingency is now impossible. Challenges Therefore, in addition tostrengthening its defense of the southwestern region and boosting the Self-Defense Forcesʼ
presence in the South China Sea and Indian Ocean, Japan is also responding to Chinese
forays by seeking to establish the rule of law in the seas and by helping capacity building inlittoral states, based on the ideas set out in the free and open Indo-Pacific.

IntroductionOn December 27, 2010, the Asahi Shimbun newspaper carried an analytical article under
the headline “Oyogi-deru kyor yū: Kokonotsu no mon” (A Mighty Dragon Swims
Out: Chinaʼs Nine Gates), arguing that China was aiming to expand into the Indianand Pacific Oceans through a series of nine “exit gates.” In the Pacific, these were aroute from the Sea of Japan through the Sōya (or La Perouse) Strait, one from the East China Sea
through the Miyako Strait and the southwestern Nansei Islands, and another from the Taiwan
Strait through the Bashi Channel. In the Indian Ocean, the routes ran from the South China Sea
through the Strait of Malacca, Sunda Strait, and Lombok Strait. The article quoted a Chinese
military source who said it was imperative for China to secure free use of these routes and gain
the ability to prevent rival powers from using them, since the routes were “kept under constantsurveillance in times of peace, and could be closed in the event of a contingency.”1
In fact, China has been conducting forays through these nine straits into the Indo-Pacific since
it first sent its navy into the Indian Ocean to help suppress piracy off the coast of Somalia in 2008.
Chinaʼs navy routinely carries out exercises and intelligence gathering in the East China Sea, andin the South China Sea China has carried out extensive reclamation projects on islands and shoalsthat are gradually being fitted for military purposes. At the same time, it regularly sends ships,*

This essay was originally published on Kokusai Mondai [International Affairs], No.687, Dec. 2019.

** Tetsuo Kotani is a professor of global studies at Meikai University and a senior fellow at the Japan
Institute of International Affairs (JIIA).
1“Oyogi-deru kyoryū: Kokonotsu no mon” (A Mighty Dragon Swims Out: Chinaʼs Nine Gates), Asahi
Shimbun, December 27, 2010.

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China’s “Nine Gates” and Security Policy in the Indo-Pacific
Challenges for Japan

including submarines, into the Indian Ocean. China already possesses what is effectively anoverseas base in Djibouti, and is generally assumed to be looking to build further overseas basesin the island nations of the Indian and Pacific Oceans as part of the Belt and Road Initiative. China
also continues to carry out actions aimed at changing the status quo in the East China Sea andSouth China Sea, through a hybrid strategy using government ships and civilian fishing vessels.
This maritime expansion is an issue of shared concern for littoral countries throughout the IndoPacific region. It is also a major challenge for Japan, from the perspective both of defending its
territory and securing the safety of its sea lanes.
This paper considers the measures that Japan should take to respond more effectively to
Chinaʼs expansion into the Indian and Pacific Oceans through these nine straits, and the policies
it should take to maintain the stability of its sea lanes and the international order based on thelaw of the sea. First, it reviews the current situation with regard to Chinaʼs forays into the Indianand Pacific Oceans through these nine straits, then evaluates Japanʼs maritime security policy in
the Indo-Pacific region. Lastly, it considers some of the ways in which Japan can respond more
effectively to Chinaʼs maritime intrusions and attempts to expand its influence.

1. China’s Forays into the Indian and Pacific Oceans

In recent years, the naval branch of the Chinese People ʼs Liberation Army (PLA) has been
increasingly active in maritime regions of the Indo-Pacific.
In the East China Sea, the PLA now routinely carries out intelligence gathering and exercisesby air and sea, and is carrying out forays into the Pacific Ocean with increasing frequency. The
point most often used as an “exit point” on these forays is the Miyako Strait. In December 2016
and June 2019, a Chinese carrier passed through the Miyako Strait with a fleet of accompanying
warships, and in January 2018 submarines were confirmed to have navigated submerged throughthe Miyako Strait into the East China Sea, demonstrating that the navy has increased its blue
water operational capability. Additionally, Chinese warships are known to have passed through theŌsumi Strait and Tokara Strait, confirming that the Chinese navy now uses various straits among
the southwestern Nansei Islands as ways out into Pacific. In the skies, reconnaissance aircraft,fighters, bombers, and electronic warfare aircraft have also flown above the Miyako Strait into the
Pacific.2 In August 2017, six bombers flew through the Miyako Strait before approaching close to
the Kii Peninsula. The US Department of Defense evaluates these flights as demonstrating that
China has the capability to attack facilities belonging to the US Armed Forces and Japanese SelfDefense Forces on Honshu.3
These incursions by the PLA into the Pacific are related to increasing Chinese pressure on
Taiwan since the government led by Tsai Ing-wen came to office in 2016. The PLA has carried out
frequent flights around Taiwan with bombers and fighters, and there have also been increasingly
frequent forays from the Bashi Channel through the Miyako Strait into the East China Sea, andfrom the Miyako Strait into the Bashi Channel.4 There have also been circumnavigations throughthe waters surrounding Taiwan by Chinese warships, including aircraft carriers. For example,
in December 2016 a Chinese carrier passed through the Miyako Strait then navigated throughthe Bashi Channel and entered the South China Sea, before passing through the Strait of Taiwan
and sailing toward the East China Sea.5 In April 2018, a Chinese carrier navigated from theSouth China Sea through the Bashi Channel into the Pacific, and from the Miyako Strait into the2Ministry of Defense of Japan, Defense of Japan 2019 Annual White Paper, September 2019, pp. 70–73.

3

US Office of the Secretary of Defense, Annual Report to Congress: Military and Security Developments
Involving the People’s Republic of China 2018, May 16, 2018, p. 119.

4

Defense of Japan 2019 Annual White Paper, p. 73.

5

Ministry of National Defense of Taiwan, National Defense Report 2017, December 2017, p. 44.

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Tetsuo Kotani

East China Sea.6 In June 2019, a carrier navigated from the East China Sea through the Miyako
Strait, then passed through the Bashi Channel into the South China Sea and through the Strait of
Taiwan, according to a report by Taiwanʼs Ministry of National Defense.7
The PLA is also moving its ships and aircraft with increasing frequency from the East China
Sea through the Tsushima Strait into the Sea of Japan. Incursions by ships into the Sea of Japanare nothing new, but in August 2016 and January 2017, navy ships and aircraft carried out naval
exercises in the Sea of Japan. Since 2017, bombers, fighters, and reconnaissance planes of theChinese air force have flown over the Tsushima Strait and entered the airspace above the Sea ofJapan, and the frequency of these incursions is increasing rapidly. The navy has also increased
its forays through the Tsugaru Strait and Sōya Strait into the Sea of Japan and the Pacific.8 In July
2019, Chinese and Russian bombers carried out joint patrols, in which planes passed from theEast China Sea over the Tsushima Strait.9
China is moving ahead with militarization in the South China Sea, where it has territorial
disputes with several neighboring countries. In the Paracel Islands, we know that China has
been extending existing runways and deploying surface-to-air missiles to the region, and there
have been confirmed take-offs and landings of fighter and bomber aircraft. Since 2014, China
has undertaken large-scale land reclamation projects at seven locations in the Spratly Islands.
It is known that China has constructed major runway facilities here, deployed surface-to-air
and surface-to-ship missiles, and installed radar jamming equipment, as well as constructing
port facilities, helipads, and radar and communications facilities.10 Although there have not yet
been confirmed take-offs or landings of fighters or bombers on the Spratly Islands, there havebeen confirmed sightings of “combat air patrols” by bombers in the South China Sea.11 If China
converted the Spratly Islands to use as a base for bombers, it would gain the ability to operate into
the Indian Ocean.12 China has also deployed strategic nuclear submarines to Hainan Island,13 andis believed to have carried out numerous submarine operations in the South China Sea.
The PLA is also active in the Indian Ocean, from the perspective of what it calls “far sea
defense” (yuanyang huwei). It has been involved in anti-piracy measures in the Gulf of Aden since2008. In 2017, China opened a de facto overseas base in Djibouti, which it is actively using forlogistics support. Under the Belt and Road Initiative, China is actively working on developing
ports throughout the region, including Kyaukphyu in Myanmar, Hambantota in Sri Lanka,
and Gwadar in Pakistan, and has taken a 99-year leasehold on Hambantota from Sri Lanka,
after that country defaulted on loan repayments. It is likely that China regards these ports as

6Defense of Japan 2019 Annual White Paper, p. 72; Joint Staff Press Release, “Chūgoku kaigun kantei nodōkō ni tsuite” (Regarding movements of ships belonging to the Chinese Navy), April 21, 2018, https://www.mod.go.jp/js/Press/press2018/press_pdf/p20180421_01.pdf.

7“Chūgoku kūbo ga Taiwan isshū: shunō kaidan-mae ni Bei kensei ka” (Chinese carrier circles Taiwan:
Possibly signaling a warning shot to the US on the eve of summit), Nihon Keizai Shimbun, June 25,
2019. https://www.nikkei.com/article/DGXMZO46556010V20C19A6910M00/.

8

Defense of Japan 2019 Annual White Paper, pp. 73–74.

9

Joint Staff Press Release, “Chūgoku-ki oyobi Roshia-ki no Higashi Shina Kai oyobi Nihonkai ni okeru
hikō ni tsuite” (Regarding flights by Chinese and Russian planes in the East China Sea and Sea ofJapan), July 23, 2019, https://www.mod.go.jp/js/Press/press2019/press_pdf/p20190723_01.pdf.

10

Defense of Japan 2019 Annual White Paper, pp. 75–77.

11

Defense of Japan 2019 Annual White Paper, p. 77.

12

US Office of the Secretary of Defense, op. cit., p. 62.

13

US Office of the Secretary of Defense, op. cit., p. 66.

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China’s “Nine Gates” and Security Policy in the Indo-Pacific
Challenges for Japanpotential future military bases.14 A Chinese submarine presence in the Indian Ocean has also
been confirmed, and Chinese submarines are known to have entered several ports in the region,
including Colombo, Sri Lanka in 2014 and Karachi, Pakistan in 2017.15 Information is lacking on
what route the Chinese Navy is using to enter the Indian Ocean, but surface shipping at least is
believed to pass through the Strait of Malacca. However, the Strait of Malacca is too shallow to besuitable for submarines, and it is likely that its submarines use either the Lombok or the Sunda
Strait.
Chinaʼs forays sometimes contravene existing international laws and rules, and represent
a threat to the freedom of navigation and freedom of the skies. Official government vessels
belonging to the Chinese Coast Guard linger in waters surrounding the Senkaku Islands on an
almost daily basis, and incursions into Japanese territorial waters happen on average aroundthree times a month.16 These incursions into Japanese territorial waters by government vessels
cannot be regarded as “innocent passage.” Similarly, navigation in the waters adjacent to the
Senkaku Islands by Chinese reconnaissance vessels, combat ships, and submerged submarines,
are provocative acts that serve to increase tensions, even if they do not count as breaches ofinternational law. The Air Defense Identification Zone that China has set up in the skies overthe East China Sea is an attempt to place all aircraft passing through the zone under the controlof the Chinese authorities; this could therefore easily impinge on freedom of overflight andother freedoms of the sky.17 Indeed, there have already been incidents in which the warningand sur veillance activities of the Self-Defense Forces and the US Armed Forces have been
obstructed.18 In June 2016, when a Chinese intelligence-gathering vessel passed through theTokara Strait in Japanese territorial waters, China argued that it regarded the strait as one
commonly “used by international navigation,” and asserted its right to pass through the waters
by right of transit passage, which involves a higher degree of freedom than innocent passage.19 In
July 2016, an arbitral tribunal constituted under the United Nations Convention on the Law of the
Sea handed down an award denying Chinaʼs “historical rights” in the South China Sea according
to its “nine-dashed line.” China refused to recognize the award, undermining the international
order based on the law of the sea.20
14

See, for example, Nicholas Szechenyi, ed., “Chinaʼs Maritime Silk Road: Strategic and Economic
Implications for the Indo-Pacific Region,” CSIS, March 2018, https://csis-website-prod.s3.amazonaws.
com/s3fs-public/publication/180404_Szechenyi_ChinaMaritimeSilkRoad.pdf.

15

Defense of Japan 2019 Annual White Paper, pp. 77–78.

16

On the activities of Chinese government ships around the Senkaku Islands, see “Senkaku shotō shūhenkaiiki ni okeru Chūgoku kōsen-tō no dōkō to wagakuni no taisho” (Movements of Chinese government
ships in the waters around the Senkaku Islands and Japanʼs response), on the website of the Japan
Coast Guard, https://www.kaiho.mlit.go.jp/mission/senkaku/senkaku.html.

17

Website of the Japanese Ministry for Foreign Affairs, “Statement by the Minister for Foreign Affairs on
the announcement on the ʻEast China Sea Air Defense Identification Zoneʼ by the Ministry of National
Defense of the Peopleʼs Republic of China,” November 24, 2013. https://www.mofa.go.jp/press/
release/press4e_000098.html.

18

Defense of Japan 2019 Annual White Paper, p. 72.

19

Nagai Ōki, “Kagoshima-oki no Tokara kaikyō, Chūgoku no ʻKokusai Kaikyōʼ shuchō ga hidane: Nihon
seifu wa ʻmitomerarezu,ʼ Gunkan haken no keizoku o keikai” (Chinaʼs claims that the Tokara Strait
off Kagoshima is open to “international navigation” creates sparks. Government of Japan refuses torecognize Chinaʼs claims, and remains on guard against continued dispatch of Chinese warships tothe area), Nihon Keizai Shimbun, digital edition, June 21, 2016, https://www.nikkei.com/article/
DGXLASFS20H6A_Q6A620C1PP8000/.

20

Kotani Tetsuo, “The South China Sea Arbitration: No, Itʼs Not a PCA Ruling,” Maritime Issues,
November 17, 2016, http://www.maritimeissues.com/south-china-sea-arbitration-ruling/the-southchina-sea-arbitration-no-its-not-a-pca-ruling.html.

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Tetsuo Kotani

As the above examples show, China is strengthening its anti access/area denial (A2/AD)
capabilities in the East China Sea and South China Sea, and is acting with increasing confidence
and brazenness based on its own unique interpretations of international law, even when atpeace. In the case of a crisis involving Taiwan, it is reasonable to assume that China now has
considerable ability to delay access to the US military and other forces. In the Indian Ocean, theestablishment of bases for maintaining long-term military operations is an issue for the future.
In the immediate term, China is likely to continue with the development of port facilities alreadyunderway in littoral states of the Indian Ocean, while expanding operations using submarines,
with their high degree of invulnerability.
Additionally, China has started to include the South Pacific in its Belt and Road Initiative, andis increasing its influence through aid to the island nations of the Pacific. China is involved in thedevelopment of four ports that observers suggest offer a high potential for military use in the
future: at Suva, Fiji; at Anewa Bay and Port Moresby in Papua New Guinea; and at Luganville,
Vanuatu.21 If these ports do come to be used by the PLA, that might lead to an increase in forays
from South China Sea via the Sulu Sea and Celebes Sea in the Western Pacific, where monitoringand surveillance by littoral states and US Armed Forces are more difficult.

2. Evaluation of Japan’s Maritime Security Policy

What steps is Japan taking in response to Chinaʼs forays onto the high seas through these ninestraits?
Firstly, Japan is strengthening its defensive capability around its southwestern Nansei Islands,
to defend against forays from the East China Sea into the Pacific. The 2010 revisions to the
National Defense Program Guidelines shifted the basic emphasis of Japanʼs defensive posturefrom the north to a new posture with an emphasis on defending against a potential threat fromthe southwest. The 2013 edition of the Guidelines defined Japanʼs objective as being to defend
the southwestern islands using a dynamic joint defense force. The plan prioritizes strengthening
Japanʼs intelligence, sur veillance, and reconnaissance capabilities in the air and seas around
Japan, and developing the ability to rapidly deploy land-based units while maintaining maritime
and air superiority. At the same time, steps were taken to increase fighter strength and deploy anairborne early warning squadron at Naha, as well as introducing stand-off missiles, increasing
submarine strength, and establishing an amphibious rapid deployment brigade and rapid
deployment units for defense of remote islands, as well as deployment to the southwestern regionof airborne early-warning units and surface-to-ship and surface-to-air guided missiles.22
These measures effectively boosted Japanʼs intelligence, surveillance, and reconnaissancecapabilities against PLA activities on sea and in the air around Japan. For example, units fromthe Air Self-Defense Force scrambled on 999 occasions through FY2018; of these, a total of
638 were in response to Chinese planes.23 However, the rapid increase in scrambling incidents
has meant that Air SDF pilots are no longer able to secure sufficient training time to prepare
for an emergency contingency. Also, Chinese aircraft flying from the Bashi Channel toward
the southwestern Nansei Islands, or along the Pacific coast of Japan, can be difficult to detect

21

Yatsuzuka Masaaki, “Chūgoku no Taiheiyō tōshokoku e no shinshutsu to ʻIttai ichiroʼ kōsō (Chinaʼs
expansion into the island nations of the Pacific and the Belt and Road Initiative), NIDS Commentary, No.
73, May 25, 2018, http://www.nids.mod.go.jp/publication/commentary/pdf/commentary073.pdf.

22

Government of Japan, “National Defense Program Guidelines for FY2014 and beyond,” December 2013,
pp. 17–24.

23

Joint Staff Press Release, “Statistics on scrambles through fiscal year 2018,” April 12, 2019, https://www.mod.go.jp/js/Press/press2019/press_pdf/p20190412_06.pdf.

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China’s “Nine Gates” and Security Policy in the Indo-Pacific
Challenges for Japanby ground-based radar, and this area is becoming something of an air defense blind spot.24
Additionally, China is rapidly modernizing its aircraft, ships, and submarines, and the qualityof the guided missiles carried by these units is also improving. It is therefore thought that a
response to an emergency contingency is becoming more difficult.
To respond to the overall improvement in Chinaʼs military strength, the 2018 revisions to the
National Defense Program Guidelines defined the nationʼs defense objectives as being to build a“Multi-Domain Defense Force” capable of executing cross-domain operations, not only on landand sea and in the air but also in the new domains of space, cyberspace, and the electromagnetic
spectrum. The thinking is that combining capabilities across domains generates synergy;
therefore, even when inferiority exists in the air or at sea, this inferiority can be overcomeand defense objectives accomplished. To this end, the guidelines included such measures asincreasing the numbers and capabilities of fighters, introducing units of hyper-velocity gliding
projectiles for defense of remote islands, strengthening monitoring and surveillance along the
Pacific through unmanned aerial systems, refurbishing the destroyer Izumo to allow operationsof short-takeoff-and-vertical-landing (STOVL) aircraft, building integrated air and missile defense
capability, establishing a new squadron specializing in space domain missions, establishing acyber defense unit, and establishing a new unit to enhance defense capability in the use of theelectromagnetic spectrum.25
Japan is also strengthening its cooperation with the United States. In the 2015 revisions to
the Guidelines for Japan-US Defense Cooperation, peacetime cooperation was expanded, andmany new fields incorporated, including intelligence, surveillance, and reconnaissance, maritime
security, training and exercises, and defense against ballistic missile attacks. In the event of anarmed attack against Japan, new areas of cooperation were added, including repelling attacks
against remote islands and cross-domain operations (including in the space and cyberspacedomains). In defending attacks against islands, the Self-Defense Forces will have primar y
responsibility for preventing and repelling ground attacks, with the United States militar y
supporting and supplementing the Self-Defense Forcesʼ operations. To ensure the effectivenessof cooperation between the allies, a new alliance coordination mechanism was establishedto strengthen policy and operational coordination, along with an upgraded bilateral planningmechanism.26
In the vital sea lanes of the South China Sea and Indian Ocean, Japan is mainly working
to support capacity building in littoral countries and to establish a stronger presence in theregion. In November 2016, Japanese Defense Minister Inada Tomomi released the Vientiane
Vision, outlining principles for defense cooperation between Japan and ASEAN. These included
consolidating order based on the rule of international law, strengthening maritime security,and support for capacity building in ASEAN in various fields. Based on this, a seminar oninternational law was held in June 2017 onboard a destroyer in the waters close to Singapore.
Japan has also offered 10 patrol vessels and two large patrol vessels to the Philippines, as wellas five TC-90 training aircraft.27 Japan altered the TC-90 deal from a lease to a free transfer, andhas also provided education for pilots in the Philippine Navy and support for maintenance staff in

24

Interview by the author with Self-Defense Forces official, April 5, 2019.

25

Government of Japan, “National Defense Program Guidelines for FY2019 and beyond,” December 2018,
pp. 10–30.

26

Ministry of Defense of Japan, “Guidelines for Japan-US Defense Cooperation,” April 27, 2015, https://www.mod.go.jp/j/approach/anpo/shishin/shishin_20150427j.html.

27

Ministry of Foreign Affairs of Japan, “Japan-Philippines Summit Meeting,” October 26, 2016, https://www.mofa.go.jp/s_sa/sea2/ph/page3e_000608.html.

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Tetsuo Kotani

the countryʼs navy and elsewhere.28 The Self-Defense Forces do not participate in the freedomof-navigation operations of the US military, but since 2017 the Maritime Self-Defense Force has
sent ships including destroyers carrying helicopters into the Indo-Pacific, and has participated in
exercises and friendship-building courtesy visits to ports in various countries around the region.29
In September 2018, a submarine from the Maritime Self-Defense Force visited Cam Ranh port in
Vietnam.30 Additionally, the Self-Defense Forces have been involved in cooperation in capability
building and exercises in the Indo-Pacific together with the armed forces of the United States,
Australia, India, the United Kingdom, France, and other countries, including in island regions of
the Pacific.
In response to the threat facing the international maritime order based on the law of the sea in
the Indo-Pacific, the National Security Strategy adopted by the Japanese government in 2013 calls
for “open and stable seas” based on international laws and conventions. To provide more concrete
substance to this vision, at the Shangri-La Dialogue (Asian Security Summit) in May 2014, Prime
Minister Abe Shinzo proposed the “three principles of rule of law,” namely: (i) making andclarifying claims based on international law, (ii) not using force or coercion in trying to drive
claims, and (iii) seeking to settle disputes by peaceful means. In August 2016, Japan launched theFree and Open Indo-Pacific (FOIP) vision, built around three main pillars, namely: 1. Promotionand establishment of the rule of law, freedom of navigation, and free trade; 2. Pursuit of economic
prosperity (connectivity, and strengthening of economic cooperation through EPAs/FTAs andinvestment agreements), and 3. Commitment to peace and stability (establishing maritime law
enforcement, humanitarian assistance, and emergency disaster relief.31 The FOIP has beenendorsed by the United States, India, Australia, the United Kingdom, France, ASEAN, and othercountries, confirming the importance of maintaining a law-based maritime order.
Challenges remain for Japanʼs maritime security policy, however. Firstly, the Bashi Channel
remains a blind spot in the countryʼs surveillance and reconnaissance. The ability to respond to
the Chinese missile threat in the East China Sea and the Western Pacific is also a major issue.
In the South China Sea, support for capability building must inevitably be limited to the nontraditional security sphere, but considering Chinaʼs maritime activities in this area, strengthening
the maritime domain awareness (MDA) capabilities of littoral states is a pressing task. Also
crucial are measures to allow monitoring of Chinese submarine movements in the Lombok andSunda Straits. There is also a need to consider a response to a possible high-end conflict in theSouth China Sea. Japan also needs to ensure that the PLA does not gain the ability to monopolize
the port facilities that China is building in island nations in the Indian and Pacific Oceans. In thelong term, the main challenge will be to maintain the rules-based maritime order in the IndoPacific, while working to change Chinaʼs distinctive interpretation of international law.

3. Issues that Japan Needs to Address for the Future

Before considering the responses Japan should take in the future, letʼs first recall what happened
during the Cold War era. When Britain withdrew its troops from East of Suez at the end of the
1960s, it created a power vacuum in the Indian Ocean. The Soviet Union advanced into the Indian
Ocean from the Pacific, threatening the sea lanes of the Western alliance. This prompted the28

Defense of Japan 2019 Annual White Paper, p. 364.

29

Japan Maritime Self-Defense Force, “Goeikan Izumo, Sazanami no chōki kōdō (2017)” (Longterm
movements of the destroyers Izumo and Sazanami, 2017), no date, https://www.mod.go. jp/msdf/
operation/cooperate/izumo-sazanami/.

30

Defense of Japan 2019 Annual White Paper, p. 362.

31

Ministry of Foreign Affairs, Summary Page: “Free and Open Indo-Pacific,” December 20, 2018, https://www.mofa.go.jp/mofaj/files/000430632.pdf.

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China’s “Nine Gates” and Security Policy in the Indo-Pacific
Challenges for Japan

United States to widen the area of responsibility of its Pacific Command in 1972, to encompass
the Indian Ocean as well as the Pacific.32 With the US Armed Forces expanding their duties
to the Indian Ocean, Japan was pressed to strengthen its defensive capabilities in the Western
Pacific. Japan boosted its monitoring, sur veillance capabilities in the Sōya, Tsugaru, andTsushima Straits, and strengthened its anti-submarine defensive capabilities and anti-warship
attack capabilities, effectively keeping the Soviet Pacific Fleet pinned within the Sea of Japan, andthereby successfully contributing to securing the safety of the sea lanes.33
Of the nine straits that China is aiming to use, five lie within Japanese territorial waters, andthe Self-Defense Forces are constantly carrying out monitoring and surveillance in these areas.
In this sense, the Cold War experience of having sealed the three straits to the Soviet Navy is
still somewhat effective as a way of warding off Chinese incursions. However, the remaining
four straits lie in the territorial waters of other nations, and since Chinaʼs A2/AD capabilities are
improving rapidly, keeping all nine straits constantly under surveillance, and closing them inthe event of a contingency is now impossible for practical purposes. For this reason, in addition
to strengthening its defense of the southwestern region and boosting the Self-Defense Forcesʼ
presence in the South China Sea and Indian Ocean, Japan is also responding to Chinese forays by
seeking to establish the rule of law in the seas and by helping capacity building in littoral states,
based on the ideas set out in the FOIP.
The first challenge for Japan in the years to come will be to improve its monitoring andsurveillance capabilities in the Bashi Channel. In particular, it is vital to be able to monitor the
movements of Chinese aircraft coming from the South China Sea through the Bashi Channel
and approaching the Nansei Islands of the southwestern region. For this, cooperation with thePhilippines and Taiwan will be essential. In the Philippines, Japan is already giving assistance
together with the United States to build MDA capacity, and cooperation is underway both within
a bilateral Japan-Philippines and a trilateral Japan-US-Philippines framework. 34 On the other
hand, security cooperation between Japan and Taiwan is politically sensitive, and the reality isthat almost no progress has been made on this so far. However, it seems likely that the PLA
will be increasingly active in the areas around Taiwan in the future, and it will be necessary toconsider a framework for sharing intelligence at the very least, perhaps with the United States asintermediary. If this could be extended to exchanges between units of the Self-Defense Forces
and the Taiwanese military, so much the better.
To respond to Chinaʼs missile threat, Japan is looking to build a comprehensive missile
defense. However, further measures will be necessary to respond to a saturated missile attackfrom China. In addition to increasing the resilience of existing facilities and dispersing themaround the country, from the perspective of making the targeting of a Chinese missile attack
more difficult, Japan should consider the joint development with the United States, which
has withdrawn from the Intermediate-Range Nuclear Forces Treaty, of a new ground-based
intermediate range missile and its deployment to Japan. Ground-based intermediate-range cruise
missiles in particular, offer cheap means of deliver y, and can easily be controlled remotely,
making them suitable for meeting the threat from Chinaʼs potential missile strength.
In the South China Sea, to boost the MDA capabilities of littoral states, Japan should help
32

Kotani Tetsuo, “Chūgoku to Taiheiyō-gun” (China and the Pacific Command), in Tsuchiya Motohiro, ed.
Amerika Taiheiyō -gun no kenkyū : Indo-Taiheiyō no anzen-hoshō (Studies on the US Pacific Command:
National Security in the India-Pacific) (Tokyo: Chikura Shobō, 2018), pp. 121–140.

33

For more on this, see Kotani Tetsuo, “Shīrēn bōei: Nichibei dōmei ni okeru ʻhito to hito no kyōryokuʼ notenkai to sono genkai” (Sea Lane defense: person-to-person exchanges in the US-Japan Alliance, theirdevelopment and limitations), in Dō shisha Hō gaku (Doshisha Law Review), Vol. 58, No. 4 (2006).

34

Interview by the author with US Armed Forces official, March 4, 2019.
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these countries to acquire and deploy radar and patrol planes. For this, it would be preferable
to cooperate not only with the United States but also with countries like Australia, the United
Kingdom, and France. In addition, a maritime monitoring system using satellites is also being
considered. This would make it possible to monitor not only the maritime areas around Japanbut global maritime areas including the South China Sea in real time.35 Rather than relying on
satellites alone, this should be made into a more comprehensive system using a variety of sensors,
including ocean buoys, and reconnaissance planes and unmanned patrol aircraft operated fromlittoral states. Japan should also cooperate with the United States, Australia, and India to boost
the anti-submarine capabilities of littoral states, to make it easier to monitor Chinese submarines
in the Lombok and Sunda Straits. Drills and exercises with Indonesia to improve operational
ability against submarines would also be effective. To prepare for the contingency of a high-end
conflict in the South China Sea, exercises should be carried out based on the assumption of USJapan cooperation, with the SDF providing rear-area and other logistical support in the event of a“situation that will have an important influence on Japanʼs peace and security.”
On Chinaʼs port developments in the island nations of the Indian and Pacific Oceans, Japan
should carry out strategic port visits in cooperation with the United States and other friendly
nations, as well as providing economic assistance to littoral states that are in danger of falling
into the “debt trap.” The Solomon Islands bent to Chinese pressure, breaking off diplomatic
relations with Taipei and recognizing Beijing, but when a provincial government tried to lease anisland to China for 75 years, the central government stepped in and rendered the deal invalid.36
This example shows that there are countries receiving Chinese aid that fear the debt trap, andillustrates the need to assist vulnerable littoral nations. In cooperation with the United States andAustralia, Japan should strengthen its presence in the Sulu and Celebes Seas that link China with
the island nations of the Pacific, and at the same time should also strengthen its maritime security
cooperation with nations like the Philippines, Malaysia, and Indonesia.
Finally, to maintain the maritime order based on the law of the sea, as well as working toestablish the FOIP on a firm footing, it will be important not to accept any double standards
from China regarding its interpretations of maritime law. In the East China and South China
Seas, China limits the freedom of navigation and overflight rights of other nations through its
own distinctive interpretations of international law, but in the Indian and Pacific Oceans enjoys
navigation rights based on the law of the sea. The United States is carr ying out freedom ofnavigation operations, and exercising its own rights within the bounds allowed by internationallaw, and is thus resisting Chinaʼs excessive jurisdictional claims. Other maritime states including
Australia, France, and the United Kingdom have also started to undertake similar operations.
Japan has been increasing the presence of the Maritime Self-Defense Force in the South China
Sea, but should also undertake operations in more sensitive maritime areas too. In particular,
given that China is increasing its activities in the East China Sea based on its own claims there,
Japan likewise needs to exercise its rights of navigation in the waters around the Paracels andSpratlys and also in the Taiwan Strait, to demonstrate clearly that it does not accept Chinese
double standards, in the event of a Chinese intrusion into Japanese territorial waters or otherunacceptable acts in waters adjacent to Japan.
35

Headquarters for Ocean Policy, Cabinet Office, “Wagakuni no kaiyō jōkyō haaku no nōryoku kyōka ni
muketa torikumi no gaiyō” (A summary of measures to strengthen Japanʼs ability to gather intelligenceon maritime conditions and developments), Minutes from the fifteenth meeting of the Headquarters for
Ocean Policy, July 26, 2016, https://www.kantei.go.jp/jp/singi/kaiyou/dai15/shiryou1_1.pdf.

36“Soromon-shotō no shima marugoto chintai, Chūgoku kigyō no keiyaku wa ʻmukōʼ genchi seifu” (Local
government in Solomon Islands declares contract to lease entire island to Chinese company “null andvoid”), AFP, October 25, 2019, https://www.afpbb.com/articles/-/3251380.

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China’s “Nine Gates” and Security Policy in the Indo-Pacific
Challenges for Japan

Conclusion
This paper discussed several issues that need to be addressed in response to Chinese forays into
the Indian and Pacific Oceans. In the Pacific, China has come a considerable way to improving
its A2/AD capacity, but in the Indian Ocean, Chinaʼs navy is still relatively weak. However,China is aiming to complete its modernization of its armed forces by 2035, and looks to become
the worldʼs leading power by the middle of this century. Sooner or later, it will surely look tostrengthen and augment its military power in the Indian Ocean too. For this reason, from a longterm perspective, it will be necessary to force China to divide its military spending between the
Indian and Pacific Oceans, to prevent it from becoming too strong in either sphere. To this end,
Japan needs to deepen strategic discussions with the United States, India, Australia, the United
Kingdom, France, ASEAN, and other countries.

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Japan Review Vol.4 No.1 Summer 2020