Sea of Japan: Resurgent
Conflict Flashpoint orStrategic Distraction?
Mr. Brent D. Sadler

Senior Fellow for Naval Warfare and Advanced Technology at the Center for National
Defense, The Heritage Foundation

This publication was produced as part of Mr. Sadler’s participation in Sasakawa Peace
Foundation USA’s In-Depth Research Trip program, which provides funding and support forparticipants to travel to Japan and engage with experts in their field to more deeply understandcommon challenges and opportunities for growth in the U.S.-Japan relationship.

Abstract
Deterring a Chinese assault on Taiwan remains a top security concern in Tokyo andWashington, which a decade-long military buildup in Japan’s southwest islands has been
critical in deterring. 1 However, this is no longer enough should Japanese domestic pressures
0F

shift after being triggered by a military crisis elsewhere, thus jeopardizing the strategic focus to
the southwest. One of several plausible incidents in the Sea of Japan could be that trigger.
Strategic distraction can be avoided with assistance by the United States with adequate military
posture and appropriate political attention to the security dynamics in the Sea of Japan.

1“Japan-U.S. Joint Leaders’ Statement: Strengthening the Free and Open International Order,” Briefing Room U.S. White House, May 23,
2022, https://www.whitehouse.gov/briefing-room/statements-releases/2022/05/23/japan-u-s-joint-leaders-statement-strengthening-the-freeand-open-international-order/ (accessed August 14, 2022).

2 Mr. Brent D. Sadler

Background
The Sea of Japan region retains important political and historical significance to the Japanesepeople. Historically, the region was important in Japan’s early modernization during the Meiji
era. Sado Island was notorious for its 400-year-long operating gold mine, closed in 1989. The
port of Maizuru near the cultural capital of Kyoto has played an important naval role. This port
served as Admiral Heihachirō Tōgō’s command and staging point for the culminating naval
battle in the nearby Tsushima Strait during the 1905 Russo-Japanese War and was a criticalconduit for raw materials feeding Japan’s World War II wartime industry.

Figure 1: Map of Japan 2

More recently, post-Cold War events here awakened Japan to pressing security dangers whenon September 1, 1998, a North Korean ballistic missile overflew the main island of Honshu.
That event triggered a Japanese response that still resonates today in the form of invigorated
defense budgets and reinterpretation of its pacifist constitutional limits on collective selfdefense. Tensions with North Korea persisted following nuclear tests beginning in 2006 and a2

Sea of Okhotsk and Sea of Japan (East Sea), Image, Encyclopædia Britannica, https://www.britannica.com/place/Sea-ofJapan#/media/1/300960/3074 (accessed August 25, 2022).

Sea of Japan: Resurgent Conflict Flashpoint or Strategic Distraction 3

second missile that overflew Japan in 2009. This newfound Japanese security activism has
likewise invigorated a more proactive regional security posture, especially after Chinese
provocations around the Senkaku Islands in 2010 and the rare earth embargo that hampered
Japanese industry. 3 Since then, it has been China’s massive military buildup and sustained
presence around the Senkaku Islands that has forced Tokyo to rebalance its military posture to
the southwest.
This rebalance was aided by successful U.S. diplomacy regarding North Korea. The Trumpadministration’s unconventional diplomatic approach ushered in a semi-détente with the Kim
regime in Pyongyang. President Donald Trump’s 2018 summit meeting with Kim Jong-un inSingapore and subsequent 2019 meeting at the demilitarized zone ushered in a period absent
long-range missile tests and nuclear weapons testing. This lull occurred as tensions flared with
China in the South China Sea and around Taiwan and was subsequently followed by diminishedpolitical focus on a subregion that has been a frequent post-Cold War flashpoint: the Sea ofJapan. The lack of political, senior military, and press attention to this region was echoed atnumerous site tours and in-person engagements I conducted over the summer of 2022.
Absent a crisis, the focus on the southwest is holding. Prime Minister Fumio Kishida recently
made new cabinet assignments in August 2022, and his choices signal continuity in Japan’s
defense policy. A policy that since 2012 has focused on the threat from China, reaffirmed byhis new Defense Minister. In his inaugural press conference on August 10, 2022, Defense
Minister Yasukazu Hamada repeated the need to improve military posture in the southwest
proximate Chinese threats to Taiwan and the Senkaku Islands. 4 This is expected given theincreased military activity by China there, but military capacities are limited and must bebalanced across a range of threats. There is the risk that military posture may become too boresighted on the threat in the southwest, allowing threats nearer to the home islands to metastasize
unchecked.

3

Carlyle A. Thayer, “The Senkaku Islands Dispute: Risk to U.S. Rebalancing in the Asia-Pacific?” USNI News, October 16, 2012,https://news.usni.org/2012/10/16/senkaku-islands-dispute-risk-us-rebalancing-asia-pacific (accessed August 18, 2022).
4
Dzirhan Mahadzir, “Japan’s New Defense Minister Looking to Improve Country’s Defense Posture Amid Chinese Aggression,” USNI
News, August 12, 2022, https://news.usni.org/2022/08/12/japans-new-defense-minister-looking-to-improve-countrys-defense-posture-amidchinese-aggression (accessed August 14, 2022).

4 Mr. Brent D. Sadler

A New Normal for Regional Geopolitics
Just as détente was materializing with North Korea, the Chinese and Russian militaries for the
first time conducted provocative combined operations in the Sea of Japan. On June 5, 2019,
Chinese President Xi Jinping and Russian President Vladimir Putin issued a joint statement in
Moscow committing both countries to an upgraded “comprehensive strategic partnership for a
new era.” 5 Then, in July 2019, Russian and Chinese long-range bombers, operating together
4F

for the first time, circumnavigated Takeshima/Dokdo Island in the Sea of Japan. Possession ofthis island is a subject of dispute between Japan and South Korea, and the ensuing
recriminations between allies over their armed forces operating in disputed airspace obscured
the more troubling Chinese and Russian activities taking place there. 6 Russian/Chinese
5F

combined air operations have been repeated since then in December 2020, November 2021,
and during a QUAD 7 summit meeting hosted in Tokyo in May 2022. 8
6F

7FThe past two years have also seen combined Russian and Chinese naval patrols in the region.
Most visible was an October 2021 combined 10-ship flotilla that sailed within easy view
through the Tsugaru Strait between Japan’s main islands of Honshu and Hokkaido. 9 At that
8F

time, Chinese ships also transited the La Perouse Strait which included the most modern
Chinese warship, a Renhai-class cruiser, which then deployed into the Bering Sea. Again in
spring 2022, another Renhai-class cruiser in a Chinese surface action group circumnavigatedJapan. This surface naval activity is in addition to Chinese and Russian combined naval andlong-range military aircraft formations that are deploying at increased frequency into the Sea
of Japan.
The U.S. Seventh Fleet based in Yokosuka, Japan is responsible for U.S. naval operations in
the region and has sustained a modest presence in the Sea of Japan. That is until the Abraham
Lincoln carrier strike group conducted operations here following renewed North Korean

5

Xinhua, “China, Russia Agree to Upgrade Relations for New Era,” June 6, 2019, http://www.xinhuanet.com/english/201906/06/c_138119879.htm (accessed November 20, 2020).
6
Jeremy Page, “China Promises Further Military Cooperation with Russia,” The Wall Street Journal, updated July 24, 2019,https://www.wsj.com/articles/china-promises-further-military-cooperation-with-russia-11563973937 (accessed November 20, 2020).
7
The QUAD is a partnership amongst India, Japan, Australia, and the U.S. formed to support a free and open Indo-Pacific. The QUAD firstemerged in 2006-2008 before atrophying, only to be later resurrected in 2017 amidst heightened tensions amongst all participants with
China. The fourth summit was held in Tokyo, Japan on May 24, 2022.
8“China, Russia fly 6 bombers over waters near Japan during Quad summit,” Kyodo News, May 25, 2022,
https://english.kyodonews.net/news/2022/05/a9eb3e528919-china-russia-fly-6-bombers-over-waters-near-japan-during-quad-summit.html(accessed August 14, 2022).
9
Brad Lendon, “Why Russian and Chinese warships teaming up to circle Japan is a big deal,” CNN, October 25, 2021,
https://www.cnn.com/2021/10/25/asia/china-russia-naval-flotilla-circles-japan-intl-hnk-ml/index.html (accessed August 14, 2022).

Sea of Japan: Resurgent Conflict Flashpoint or Strategic Distraction 5

intercontinental ballistic missile tests in March 2022. 10 This was the first time in five years thata carrier strike group had operated in these waters. However, it is recurring bilateral exercisesthat are most critical to maintain and enhance interoperability amongst allies, such as the
Bilateral Advances Warfare Training (BAWT). The last iteration of BAWT was over February
28 to March 2, 2022, occurring in the Philippine Sea. 11 Importantly, most bilateral exerciseswith the Japan Maritime Self Defense Forces (JMSDF) are not conducted in the Sea of Japan,
instead favoring large weapons ranges, uncontested air space, and a desire to conduct sensitive
training further from Chinese and Russian interlocutors.

Emerging Operational Patterns
The Need for Missile Defense
Even as North Korean provocations return and the operational tempos of Chinese and Russian
militaries in the Sea of Japan pick up, the U.S. and Japan Self Defense Forces (SDF) posture
has not yet changed. In fact, the attempt to base two AEGIS ashore sites in the region falteredon poor community outreach and operational planning with regard to ascertaining rocket
booster drop zones. 12 Yet the need for missile defense from North Korea persists. Japan has
two ballistic missile defense (BMD)-capable destroyers—Atago and Myōkō, both based in
Maizuru—but a persistent defense requires additional BMD-capable destroyers not anticipatedto arrive until 2027.13 Immediate missile defense requires redeploying destroyers from other
districts or deploying Seventh Fleet ships based in Yokosuka, Japan. This means having lesspresence or capability elsewhere—notably in the South China Sea—and diminished ability toprovide missile defense for the strategically important U.S. territory of Guam.
In the mid-term (two to five years), recently or to-be decommissioned BMD-capable U.S.
Ticonderoga-class cruisers might be able to fill the gap. These ships were designed to provide
air defense to carrier strike groups, with later upgrades for ballistic missile defense. Aging
Ticonderoga-class cruisers with limited BMD capabilities have been recently decommissioned

10

Diana Stancy Correll, “USS Abraham Lincoln operating in Sea of Japan following North Korea missile tests,” Navy Times, April 12,2022, https://www.navytimes.com/news/your-navy/2022/04/12/uss-abraham-lincoln-operating-in-sea-of-japan-following-north-koreamissile-tests/ (accessed August 14, 2022).
11
Commander, Task Force 71/Destroyer Squadron 15, “U.S. Navy and JMSDF join forces for advanced training,” Commander U.S. PacificFleet, March 4, 2022, https://www.cpf.navy.mil/News/Article/2955565/us-navy-and-jmsdf-join-forces-for-advanced-training/ (accessed
August 14, 2022).
12
Jeffrey W. Hornung, “Japan Is Canceling a U.S. Missile Defense System,” RAND Corporation, July 6, 2020,
https://www.rand.org/blog/2020/07/japan -is-canceling-a-us-missile-defense-system.html (accessed August 12, 2021).
13
Yoshihiro Inaba, “Japan Moves Forward With Aegis Equipped Ship Project. But Is It Enough?,” Naval News, October 11, 2021,
https://www.navalnews.com/naval-news/2021/10/japan-moves-forward-with-aegis-equipped-ship/ (accessed August 14, 2022).

6 Mr. Brent D. Sadler(or are awaiting to be). 14 Their older analog radar systems, while still capable, have a limited
capacity for engaging advanced missiles or multiple targets, but would be adequate against a
North Korean ballistic or cruise missile threat. Manning these ships in a reduced operational
condition provides several advantages. First, as a moored platform it can be relocated as thethreat and deconfliction with local activity merits—recalling AEGIS ashore was cancelled due
to local concerns over missile booster rocket drop sites. Second, the insertion of up to 244
vertical launch cells of two such ships bolsters regional defenses and complicates Chinese war
planning. Third, it provides a platform to train Japan’s SDF forces who may eventually operate
future BMD-capable Japanese-built warships or a resurrected AEGIS ashore option. Lastly,
there is the potentiality of transferring such cruisers to Japan to be operated as BMD platforms
through what is called a “hot ship transfer,” avoiding de/re-activation costs. 15 However, thisoption also allows a pathway for developing limited SDF strike capacity since these ships areplatforms for targeting and employing tomahawk cruise missiles.

Increased Demands on the JASDF
As Chinese and Russian air patrols in the region increase, this will add to Japan Air SDF(JASDF) operational demands as well. Since 2004, the SDF have been recording historic levels
of intercepts, peaking at 1,168 sorties in 2016 leveling at 725 in 2020. 16 Since 2011, themajority of these Japanese responsive air sorties were due to Chinese air activities in thesouthwest. If Chinese and Russian air activity increases in the Sea of Japan, it increases thegeographic range needing to be covered by the SDF. This will pose new coordination andcapacity challenges for the JASDF and potentially for U.S. aircraft based in Okinawa, Misawa,and Iwakuni. It is worth noting that increased Chinese air operations were taxing existing
forces, resulting in new intercept policies implemented in 2020 to launch only whenencroachments directly threatened Japanese territorial airspace—which had the subsequent

14

Heather Mongilion, “Navy Wants to Decommission 39 Warships in 2023,” USNI News, August 15, 2022,
https://news.usni.org/2022/08/15/navy-wants-to-decommission-39-warships-in2023#:~:text=Already%2C%20the%20Navy%20recevied%20permissioned,.%204%2C%20USNI%20News%20reported (accessed August19, 2022).
Chief of Naval Operations, “Report to Congress on the Annual Long-Range Plan for Construction of Naval Vessels for Fiscal Year 2022,”
June 2021, p. 12, https://s3.documentcloud.org/documents/20961220/pb22-shipbuilding-plan-june-2021_final.pdf (accessed August 10,2021).
15
Thomas B. Modly, “TRANSFER OF U.S. NAVAL VESSELS TO FOREIGN GOVERNMENTS
AND INTERNATIONAL ORGANIZATIONS,” Secretary of the Navy Instruction 4900.50B, May 9, 2019, p. 4-5,
https://www.secnav.navy.mil/doni/Directives/04000%20Logistical%20Support%20and%20Services/04900%20Foreign%20Military%20Assistance%20and%20Mutual%20Security%20Services/4900.50B.pdf (accessed August 19, 2022).
16“Defense of Japan,” Ministry of Defense, 2021, pg. 15, 17-18 and 25,
https://www.mod.go.jp/en/publ/w_paper/wp2021/DOJ2021_Digest_EN.pdf (accessed August 14, 2022).

Sea of Japan: Resurgent Conflict Flashpoint or Strategic Distraction 7

effect of slightly reducing reported air intercepts. 17 Given the sensors and air defense weapons(e.g., SM-3, SM-6) of the above BMD-capable warships, their entry into the region mitigatessomewhat the burden on JASDF and U.S. aircraft.

New and Preexisting Submarine Threats
Additionally, it must be assumed that advanced Chinese and Russian submarines will be
operating at increased frequency in the Sea of Japan. During the recent Russian and Chinese
combined naval operations there, the Russian press did mention a Chinese submarine wasparticipating. These submarines will add to the already present threat of North Korea’s soleantiquated ballistic missile submarine; potentially armed with a nuclear capable missile. 18
Given the nuclear threat this antiquated submarine poses, it will require naval assets to monitor.
While the North Korean submarines do not pose a daunting technical challenge, the same is notnecessarily true for more advanced modern Chinese and Russian submarines added to this mix.

Current U.S. and JMSDF Capabilities and Cooperative Activities
JMSDF’s Maizuru district is responsible for securing Japan’s maritime interests in the Sea ofJapan and consists of Escort Division 14, Escort Division 3, Minesweeper Division 44, andseveral supporting commands. However, it is the capabilities of the escort divisions that are
most relevant to countering Chinese, Russian, and North Korean naval incursions. Escort
Division 3 consists of flag ship Hyūga, a large helicopter-carrying destroyer, and three
destroyers: the Fuyuzuki, and BMD-capable Myōkō and Atago. Importantly this division istasked with being able to deploy out of the Maizuru district and has previously participated in
multinational exercises such as Rim of the Pacific (RIMPAC) in Hawaiian waters and Malabar
off of Okinawa in 2016. Escort Division 14 is comprised of three legacy (30+ years old)
destroyers intended for anti-submarine operations: destroyers Asagiri and Setogiri with hull andtowed sonars, and destroyer escort Sendai with hull sonar only. All three are able to deploy asingle SH-60J/K helicopter. The two modern Asahi-class destroyers optimized for antisubmarine warfare are the Shiranui based in Ōminato district covering the northern pacific, and
the Asahi based in Sasebo covering the southwest region. No additional ships of this class are

17

Clement Charpentreau, “Japan Reduces Chinese Interceptions as it Deploys F-35s,” Aerotome Hub, March 4, 2021,
https://www.aerotime.aero/articles/27398-japan-reduces-chinese-interceptions-as-it-deploys-f-35s (accessed August 14, 2022).
18
Choe Sang-Hun, “North Korea Tests a Submarine-Launched Missile,” The New York Times, May 7, 2022,
https://www.nytimes.com/2022/05/07/world/asia/north-korea-missilesubmarine.html#:~:text=North%20Korea%20has%20only%20one,submarine%2Dlaunched%20ballistic%20missile%20program (accessed
August 15, 2022).

8 Mr. Brent D. Sadler
currently planned. This situation will likely see increased demand for a U.S. anti-submarine
presence as well as both JMSDF and in short supply U.S. nuclear submarines to patrol thesewaters.
However, adding more warships—even repurposed legacy ships in reduced operational
status—introduces logistic burdens that must be considered. For the U.S. Seventh Fleet,maintaining any additional ships will tax its ship repair facilities (SRF) in Yokosuka and
Sasebo. Since 2014, both these shipyards have seen persistent delays due to planned
maintenance, which would be exacerbated with additional ships to service unless underlying
causes are addressed and SRF capacities in Japan are grown. A 2020 Government
Accountability Organization report on overseas surface ship maintenance recommend that the
Secretary of the Navy develop a comprehensive (overseas and domestic) maintenance plan toinclude plans for expanding maintenance capacities. 19 To date, there has been no reported
progress on these recommendations.
As part of basing agreements, significant host nation support is provided to sustain the Seventh
Fleet. For example, all Japanese employee salaries at these SRFs are paid by the governmentof Japan; the current agreement raised the preexisting limit from 18,217 to 19,285 employees
whose salaries it will pay. 20 Leveraging this assistance at new locations affords one method tomitigate the workload on Sasebo and Yokosuka SRFs by sending some U.S. ships to wherecomparable JMSDF ships do repairs. Should U.S. ships do repairs away from Sasebo or
Yokosuka, it will necessitate families being separated as American schools and housing are colocated at those bases. This will necessitate rethinking Seventh Fleet’s forward deployed naval
force three-month deployments to longer periods that include remote Japan maintenanceperiods.
Sending U.S. warships to do maintenance at Japanese shipyards is not a novel idea; in fact, it
is already being done. One example is the destroyer Milieus that conducted repairs in April
2019 at Mitsubishi Heavy Industry’s Yokohama dockyard near its homeport of Yokosuka. 21

19

Diana Maurer, “NAVY SHIP MAINTENANCE: Actions Needed to Address Maintenance Delays for Surface Ships Based Overseas,”
Government Accountability Office, February 2020, p.6, 43 and 55-56, https://www.gao.gov/assets/gao-20-86.pdf (accessed August 19,2022).
20“Entry into Force of the New Special Measures Agreement (SMA),” Ministry of Foreign Affairs and Japan, April 1, 2020,
https://www.mofa.go.jp/region/n-america/us/security/hns.html (accessed August 19, 2022).
21
USS Milieus homepage, update June 30, 2022, http://www.uscarriers.net/ddg69history.htm (accessed August 20, 2022).

Sea of Japan: Resurgent Conflict Flashpoint or Strategic Distraction 9

As for the BMD-capable AEGIS ship Myōkō, it splits its maintenance between Nagasaki for
AEGIS-related repairs and general maintenance in Maizuru with the other naval district ships
based there. Japan Marine United is contracted to support JMSDF ships in Maizuru. 22 Nonnaval workload in Maizuru has diminished due to South Korean and Chinese competition forcommercial contracts.

Okinawa’s Political Impact on Burden-Sharing
Looking to balance the maintenance burden outside of Sasebo and Yokosuka, while keeping
this activity in Japan, will run into a thorny domestic political issue: the basing burden on
Okinawa. For years, the Okinawan people have protested what they view as an unfair burden
for hosting the majority (more than 70%) of U.S. forces in Japan, and have fueled efforts torelocate U.S. Marine Corps bases off-island. 23 That effort was part of the now stalled 2002
Defense Policy Review Initiative (DPRI), which has only partially relocated marines off
Okinawa and constructed a replacement base in Okinawa at Henoko. 24 The issue is a national
one; at a ceremony commemorating the 50th anniversary of Okinawa’s 1972 reversion to Japanattended by the Emperor and the Governor of Okinawa, Prime Minister Fumio Kishidacommitted to lessening the burden on Okinawans. 25 By looking to SDF bases such as Maizuru
for greater support, both the Japanese and U.S. governments would demonstrate their efforts tolessen this burden on Okinawa while also mitigating SRF workloads as the overall naval
presence in Japan grows to meet the combined threat from China, Russia, and North Korea.

Illicit Maritime Activity by China, North Korea, and Russia
Lastly, illicit trade has been an issue in the region, though effectively countered ashore by theJapanese police. That said, illegal fishing poses a growing problem with the arrival in recent
years of large Chinese fishing fleets licensed to fish in North Korea’s exclusive economic zone
(EEZ). Pressure on regional fishing stocks from aggressive Chinese fishing fleets has become
more pronounced since 2016 when a large Chinese fishing fleet sheltered at the South Korean

22
23Japan Marine United Corporation, https://www.jmuc.co.jp/en/ (accessed August 20, 2022).

“Okinawa urges PM to scrap U.S. base move plan before key anniversary,” Kyodo News, May 10, 2022,
https://english.kyodonews.net/news/2022/05/591d25652c39-okinawa-urges-pm-to-scrap-us-base-move-plan-before-key-anniversary.html(accessed August 19, 2022).
24
Emma Chanlett-Avery, Joshua Williams and Caitlin Campbell, “The U.S.-Japan Alliance,” Congressional Research Service, June 13,
2019, p. 28-29, https://sgp.fas.org/crs/row/RL33740.pdf (accessed August 15, 2022).
25“50th Anniversary Ceremony held in Okinawa and Tokyo,” Okinawa Prefectural Government, May 19, 2022, https://dcoffice.org/post/1675#:~:text=Prime%20Minister%20Fumio%20Kishida%2C%20in,efforts%20to%20reduce%20the%20burden (accessed
August 19, 2022).

10 Mr. Brent D. Sadler
island of Ulleung-do. 26 That event heavily taxed local waterfronts and for a time gained someinternational attention. There are indications these fleets are forcing fish stocks to migrate as
they overfish North Korean waters. One consequence has been so-called North Korean ghost
ships washing ashore in Japan with their North Korean crews dead or dying from exposure after
being unable to return to port. 27
Overfishing is also driving Chinese fishing fleets to follow the fish and squid into South Korean
and Japanese waters. Policing this activity falls on the Japan Coast Guard (JCG). Additionally,
as sanctions on Russia persist for its invasion of Ukraine, there will be increased pressure to
circumvent them. In the past, Japanese used cars have been a key commodity in the Russian
Far East, and there has been a black-market trade in Russian seafood. As such, the JCG could
see its mission loading increase to counter Russian smuggling as well as Chinese fishing fleet
encroachment, potentially drawing in more naval presence to assist with detecting and tracking
illicit activities which the JCG would then intercept.
To address illicit activities in the Sea of Japan, the Japan Coast Guard operates cutters in three
regions: 2nd, 8th, and 9th. From seven ports in these three regional commands are deployed ten
patrol vessels and three cutters capable of embarking helicopters; an additional three patrol
vessels operate from Otaru and Wakkanai on Hokkaido facing the Sea of Japan. These patrol
vessels and larger cutters are augmented by seven medium and small maritime patrol aircraft. 28
This force is expected to patrol the Japanese economic exclusive zone where in recent years
China has operated 148 open ocean fishing vessels in the Sea of Japan. 29

Capacity Gaps and Priorities
Matching every Chinese, Russian or North Korean military operation is not required, but
responding effectively to a politically sensitive event is. Striking the right balance amongst
these threats and establishing appropriate priorities will be critical to sustaining the main effort
to the southwest. Several Sea of Japan trends should inform planning for what forces are needed
to mitigate any politically significant crisis in the near-term (next five years):
26

Ian Urbina, “The deadly secret of China's invisible armada,” NBC News, July 22, 2020, https://www.nbcnews.com/specials/china-illegalfishing-fleet/ (accessed August 14, 2022).
27
Ian Urbina, “The origin of North Korea's 'ghost boats’,” BBC, September 9, 2020, https://www.bbc.com/future/article/20200909-theorigin-of-north-koreas-ghost-boats (accessed August 20, 2022).
28
Japan Coast Guard, “Organization,” April 1, 2020,
https://www.kaiho.mlit.go.jp/e/organization/pdf/deployment_status_of_large_patrol_vessels.pdf (accessed August 14, 2022).
29
Discussions with staff at Japan Coast Guard headquarters in Tokyo, Japan on 1 July 2022.

Sea of Japan: Resurgent Conflict Flashpoint or Strategic Distraction 11

1. North Korea is likely to continue its long-range missile launches, nuclear testing, androutinized deployments of its ballistic missile submarine. Such activities necessitate
renewed emphasis on missile defense and increased capacity to track North Korea’s
submarines, especially its nuclear ballistic missile submarine.
2. Already China and Russia have conducted routine combined naval and air missions in
the region. To date since 2019 these have been short in duration, but it is likely future
operations will evolve into a more prolonged presence to include live fire drills, as is
the case elsewhere.
3. As fish stocks in North Korean waters are depleted by large Chinese fishing fleets, there
will be pressure to find new fishing areas in the Sea of Japan. This could see large
Chinese fishing fleets in Japanese waters as well as South Korean waters. The most atrisk fishing area for this activity is the Yamato ridge located deep in the Sea of Japan(but still within Japan’s exclusive economic zone). 30 Compounding this problem is the
29 F

absence of any agreed framework for Japanese and South Korean coast guards to work
together and police their waters from overfishing and illegal activity.
4. There will likely be increased illegal activity emanating from sanctions avoidance by
North Korea and increasingly Russia. There is a long history of Russian trade in usedcars that skirts legality (160,000 were exported from Japan to Russia in 2021), as well
as stolen luxury cars and illegal fishing via routes that cross the Sea of Japan. 31 One
area already straining under sanctions in Russia’s Far East is access to auto parts andreplacement cars; they will likely see resurgent demand for autos from Japan in stolen
and used cars. 32 In short, the need to police increased illicit activity will place addedcomplexity and operational pressures on allied maritime forces in the Sea of Japan.

30“日本海大和堆の違法中国漁船が激減水産庁,” TV-Asahi, video, August 5, 2022, https://news.tvasahi.co.jp/news_economy/articles/000264091.html (accessed August 14, 2022).
“大和堆（やまとたい）で北朝鮮の違法操業が深刻化日本の漁業者苦境,” SankeiBiz, January 9, 2020,
https://www.sankeibiz.jp/workstyle/news/200109/cpd2001090857001-n1.htm (accessed August 14, 2022).
31“Russia-Ukraine conflict buffeting Japan’s used-car market,” Asian News Network, April 21, 2022, https://asianews.network/russiaukraine-conflict-buffeting-japans-used-car-market/ (accessed August 14, 2022).
“Japan charges Russians stole 140 cars,” World News, September 28, 2012, https://www.upi.com/Top_News/WorldNews/2012/09/28/Japan-charges-Russians-stole-140-cars/99611348846514/ (accessed August 14, 2022).
32
Andrew Roth and Pjotr Sauer, “The return of banditry’: Russian car industry buckles under sanctions,” The Guardian, June 11, 2022,
https://www.theguardian.com/world/2022/jun/11/the-return-of-banditry-russian-car-industry-buckles-under-sanctions (accessed August 14,2022).

12 Mr. Brent D. Sadler

5. Lastly, one wartime scenario is worth addressing due to its implications to the U.S.Japan alliance: a Chinese threat or actual attack using tactical nuclear weapons against
at-sea JMSDF forces. According to my conversations with Professor Narushige
Michishita of the Graduate Institute for Policy Studies (GRIPS) located in Tokyo, Japan,such a scenario strikes at a weakness of U.S. extended deterrence assurances and fears
in Japan of being caught in a costly war. This seemingly implausible event does fit with
Chinese military doctrine and should not be discounted outright. China might be
inclined to make such threats or attack hoping to limit Japan’s support for a war overTaiwan by taking advantage of a missing rung in the U.S. strategic escalation ladder.
That is, the absence of viable U.S. tactical nuclear weapons such as the submarinelaunched cruise missile, which is currently hotly debated in the U.S. Congress. 33
Unaddressed, this strategic gap undermines confidence in extended deterrence
assurances encapsulated in the U.S.-Japan alliance. While China’s use of a tactical
nuclear weapon against JMSDF forces at-sea could be done in the East China Sea to theNorth Pacific, it is the threat of such use in the context of increased tensions in the Sea
of Japan that could be more problematic and more likely. By threatening Japan’s naval
forces in the Sea of Japan with a tactical nuclear weapon, the United States would beunable to respond in kind, and the remoteness of the attack would seemingly negate
greater escalation. However, a similar provocation closer to Tokyo, major Japanese
population centers, or U.S. bases would likely entangle the United States directly andtrigger unwanted escalation and rally popular support—all contrary to Chinese strategic
intentions to diminish the U.S.-Japan alliance and keep Japan out of a war over Taiwan.

Recommendations
A balanced approach is needed that sustains the prioritization of military resources to southwest
Japan, while maintaining the ability to adequately address the risks emanating across the Sea
of Japan. To achieve this, the following are offered for consideration:

33

Patty-Jane Geller and Brent Sadler, “Faulty Assumptions About the Global Nuclear Threat May Require Changes in U.S. Sea-Based
Nuclear Force,” The Heritage Foundation, February 22, 2022, https://www.heritage.org/defense/report/faulty-assumptions-about-the-globalnuclear-threat-may-require-changes-us-sea-based.

Sea of Japan: Resurgent Conflict Flashpoint or Strategic Distraction 13

The U.S. National Security Advisor and Japan’s National Security Secretariat
should prepare combined national-level responses to provocations in the Sea ofJapan.
The 2015 Defense Guidelines’ Alliance Coordination Mechanism, if fully utilized, can enable
this sort of planning and coordination during a crisis, as well as provide a platform fororchestrating more proactive strategic initiatives. 34 This mechanism as envisioned would
enable iterative and ongoing planning between the Japan National Security Secretariat and the
U.S. National Security Council.
Additionally, within this mechanism a working group should be established with the specifictask of enhancing combined naval presence and crisis response in the Sea of Japan. Learningfrom the DPRI, this group would sustain national political attention as it works through tricky
political and budgetary arrangements required to achieve basing adjustments and long-range
deployment planning. While there are numerous reasons why this highly complex initiative
stalled, it and similar efforts recommended here would benefit from having easy access to seniornational leadership to ensure progress.

The U.S. Secretary of State and Japan’s Minister of Foreign Affairs work
together in pursuit of agreement for coordinated coast guard operations between
Japan and South Korea to enforce common maritime law with regard to illegal,
unreported, and unregulated fishing (IUU), sanctions violations, etc.
As Russia’s economic isolation tightens, there will be increasing pressures for smuggling (cars,
seafood, etc.) across the Sea of Japan to sustain Russia’s Far East. This increased illegal activity
will place added strain on the JCG already adjusting to increased Chinese fishing activity. A
memorandum of understanding with South Korea is one possibility for devising methods ofsharing the workload of maritime security as illicit activity increases in the near-term.

34“The Guidelines for Japan-U.S. Defense Cooperation,” Ministry of Foreign Affairs of Japan, April 27, 2015, p. 3,
https://www.mofa.go.jp/files/000078188.pdf (accessed August 15, 2022).

14 Mr. Brent D. Sadler

The Japan Minister of Defense should request and the U.S. Secretary of Defense
should offer Japan a near-term alternative to the cancelled AEGIS ashore.
One option is to repurpose recently or soon-to-be decommissioned BMD-capable U.S.
Ticonderoga-class cruisers as a moored defense platform. 35 These ships, while limited in theirability to defend against high-end Chinese and Russian missile threats, provide the JMSDF a
familiar platform after decades of experience with the Kongo-class and its successors.

The Japan Minister of Defense and U.S. Secretary of Defense should negotiate
greater access and support for U.S. vessels at JMSDF bases in the Sea of Japan.
Doing this would enable longer deployments to the region and develop a distributed logistic
network. This would also mitigate longstanding complaints of the basing burden in Okinawa
and relieve some maintenance work of SRFs in Yokosuka and Sasebo. 36

The U.S. Chief of Naval Operations should extend deployments of modern andcapable anti-submarine platforms to the Sea of Japan.
The JMSDF has limited anti-submarine capacity in the Sea of Japan to prosecute modern
Chinese and Russian submarines without drawing from other maritime districts. Forces once
adequate for meeting an inferior North Korean submarine threat and limited Russian presence
are no longer adequate as China increasingly operates modern submarines in this region.
Additionally, U.S. and South Korean navies should be invited to participate in increasingly
complex anti-submarine exercises in the region, while routinizing coordinated trilateral patrols.

The Dangers of Inaction
The primary theater of operations—and where strategic risk is greatest this decade—remains
the waters around Taiwan. That being said, there is danger that a significant incident could
create insurmountable domestic pressures to refocus on the Sea of Japan region at the expenseof deterring a Chinese military assault on Taiwan.

35

Brent Sadler, “Repurposing Navy Cruisers Planned for Decommissioning: An Interim Capability for Countering Chinese Missile Attacks
on Guam,” The Heritage Foundation, August 23, 2021,https://www.heritage.org/defense/report/repurposing-navy-cruisers-planneddecommissioning-interim-capability-countering (accessed July 21, 2022).
36“Nearly 80% of Japanese think Okinawa's base-hosting burden unfair,” Kyodo News, May 5, 2022,
https://english.kyodonews.net/news/2022/05/91ffa894f1f3-nearly-80-of-japanese-think-okinawas-base-hosting-burden-unfair.html (accessed
August 15, 2022).

Sea of Japan: Resurgent Conflict Flashpoint or Strategic Distraction 15

To avoid this, institutional awareness of the potentiality of a Sea of Japan crisis anddevelopment of appropriate response plans that do not jeopardize deterrence in southwest Japanare needed. This is not a binary choice between two theaters of operation, but rather striking
the appropriate balance of forward maritime security presence. Today, U.S. and JMSDF forcesin the Sea of Japan alone may not be adequate without new basing arrangements anddeployment patterns, at a minimum.

Brent Sadler joined Heritage Foundation after a 26-year Navy career withnumerous operational tours on nuclear powered submarines, personal staffs ofsenior Defense Department leaders, and as a military diplomat in Asia. As asenior research fellow, Brent’s focus is on maritime security and the technologies
shaping our future maritime forces, especially the Navy.
Brent is a native of Springfield, Virginia, and a 1994 graduate with honors of theUnited States Naval Academy with a degree in Systems Engineering (robotics)
and a minor in Japanese. As a 2004 Olmsted Scholar in Tokyo, Japan, he studied
at Keio University, Jochi University and the United Nations University. He has a
M.A. from Jochi University and M.S. from National War College where he graduated with distinction in 2011
receiving several writing and research awards.
In 2011, he established the Navy Asia Pacific Advisory Group (NAPAG), providing regionally informed advice
directly to Chief of Naval Operations’ (CNO). He again served on the CNO’s personal staff in 2015-2016, playing
a key role in developing the Defense Department’s Third Offset.
At Pacific Command from 2012-2015, he held numerous key positions. As lead for Maritime Strategy and Policy,
he incorporated all 10 Association of Southeast Asian Nations (ASEAN) into the first regional maritime domainawareness forum; and, was instrumental in the eventual passage of the $500 million dollar Maritime Security
Initiative. As Special Advisor on Japan, and a Council of Foreign Relations International Affairs Fellow in Tokyo,
he played a key role in revising the U.S. and Japan Defense Guidelines. As Deputy Director Strategic
Synchronization Group, he oversaw a think-tank like body of over 30 advisors and analysts. Brent led theCommander’s Rebalance Task Force coordinating execution of the President’s Defense Strategic Guidance—
Rebalance to the Asia-Pacific resulting in over $12 billion USD of additional monies budgeted in fiscal years 2013
through 2015 during a time of fiscal austerity.
Following his final tour on CNO’s staff, Brent returned to Asia as Senior Defense Official, Defense and Naval
Attaché in Malaysia. During his tenure he played a key role in coordinating responses to the USS McCain collisionin August 2017, opened several politically sensitive ports and airfields to U.S. forces, oversaw unprecedented
expansion of U.S. military relations, and steadied relations during the historic May 2018 national elections
ushering in an opposition party for the first time since independence.
His final Navy assignment was China Branch of Navy Staff at the Pentagon. He is married to the former Yulia
Polyakova and has two daughters: Sophia and Vivienne.