The year 2023 was a turning point for Japan-South Korea relations. There was a breakthrough in the issue of compensating forced laborers, which led South Korean President Yoon Suk Yeol and Japanese Prime Minister Kishida Fumio to meet seven times since their summit in March. Shuttle diplomacy has been fully resumed. By year’s end, their cooperation in new areas such as energy, critical and emerging technology, development and humanitarian assistance, space, and cyber is blossoming. Last year will be remembered as the year that began to demonstrate a real potential for Seoul and Tokyo to be like-minded global partners, along with Washington. If the first half of 2023 was a speed chase to get to the finish line—the Camp David trilateral summit meeting—the latter half of 2023 was a coordinated plan to prepare for many more races. As noted in our last issue of Comparative Connections, the Camp David trilateral summit represented a potential harbinger for the future of Japan-Korea relations.

First, the trilateral summit signified South Korea’s commitment to “actively participat[ing] in shaping the future of regional and international order” to an unprecedented level. Second, it suggested potential for Japan and South Korea to be “like-minded partners beyond consultations over North Korea, seeking to shape the contours of international affairs in the Indo-Pacific.” Third, Seoul, Tokyo, and Washington “took huge strides towards institutionalizing and strengthening security cooperation.” Fourth, they agreed on “an ambitious schedule of trilateral dialogues.” And fifth, they decided to cooperate on economic security issues such as global supply chain disruptions. 

The final months of 2023 witnessed Japan and South Korea focusing intently on implementing the deliverables, which showed the “extraordinary degree of alignment” at all levels and in different strategic priorities, to quote Mira Rapp-Hopper, National Security Council senior director for East Asia and Oceania, present at Camp David. There have been 30 trilateral meetings since Aug. 18, a blistering pace of a trilateral meeting every 3.5 days, and at various levels. While these meetings may seem normal now, it was unthinkable just a year ago, especially considering how many observers thought Seoul-Tokyo relations were at the lowest point since the 1965 normalization. 

Diplomacy and Dialogues Thrive

Bilateral diplomacy continued at all levels, leading President Yoon to declare in November that “all government-to-government dialogue mechanisms that the two countries had agreed on in March have been restored [100%].” Since March 2023, President Yoon and Prime Minister Kishida have met seven times, including a meeting on the sidelines of the G20 summit in New Delhi in September, one on the sidelines of the APEC meeting in San Francisco on Nov. 16, and a trilateral meeting with President Biden. Yoon and Kishida also went to Stanford University together for a rare joint event (first time ever in a third country). 

It is no exaggeration to say that the two leaders’ diplomatic activities add up to the implementation of the Camp David Principles as like-minded partners and shapers of international affairs in the Indo-Pacific. For example, their joint appearance at Stanford in November signaled to the world what they are seeking to accomplish—Seoul-Tokyo partnership over science and technology, the field that lies at the intersection of national security and economy. They discussed quantum technology, clean energy and innovation. In line with their commitment to addressing economic security issues together, the two leaders announced the Hydrogen Ammonia Global Value Chain. Under this framework, Japan and South Korea seek to build a global value chain of hydrogen and ammonia, considered crucial in terms of the goals of decarbonizing their economies. To strengthen collaboration in science and technology, Japan’s National Institute of Advanced Industrial Science and Technology and the Korea Research Institute of Standards and Science will sign a memorandum of understanding; the University of Tokyo, Seoul National University, and the University of Chicago will collaborate, as well. During their visit to San Francisco, President Yoon and Prime Minister Kishida also spoke with Korean and Japanese startups working in Silicon Valley. Korea reportedly has plans to open a Korea Startup Center in Tokyo in 2024 to facilitate startup exchanges between Korea and Japan. 

Figure 1 At an event hosted by Stanford University on November 17, South Korean President Yoon Suk Yeol, on the left, and Japanese Prime Minister Fumio Kishida, on the right, participated, with former U.S. Secretary of State Condoleezza Rice serving as the moderator in the center. Photo: Office of the President South Korea

Prime Minister Kishida and President Yoon also continued to voice support for the bilateral relationship. On Oct. 23, Kishida, during his policy speech to the 212th session of the Diet, reconfirmed the importance of Japan’s relations with South Korea, stating that he is deepening bilateral engagement with Seoul based on the personal trust he shares with President Yoon. At a meeting with members from the Korea-Japan Friendship Association and the Japan-Korea Friendship Association on Oct. 13, Yoon said he believes they can “open a new future over and beyond the period when South Korea-Japan relations were at their best.” Likewise, in his message to a group of senior political and business leaders from both countries on Oct. 23,  Kishida called upon a “new era” of bilateral relations between “important neighbors…working together on various challenges in the international community.”

In mid-September, Prime Minister Kishida reshuffled his Cabinet, and replaced his long-time Foreign Minister Hayashi Yoshimasa who has been at the center of his rapprochement and trilateral efforts, with Kamikawa Yoko, a former three-time justice minister. Hayashi was later brought back by Kishida to serve as his chief Cabinet secretary in mid-December. Not long after taking office, Foreign Minister Kamikawa met South Korean Foreign Minister Park Jin on the sidelines of the United Nations General Assembly in New York, where they discussed the bilateral relationship and North Korea. She also had her first trilateral foreign minister meeting the day after, where they discussed trilateral cooperation and North Korea-Russia arms cooperation with US Secretary of State Antony Blinken. 

On Oct. 5, Korea and Japan resumed vice-ministerial strategic dialogue for the first time in nine years. Participating in that dialogue was First Vice Foreign Minister Chang Ho-jin, who was named by President Yoon in late December as his new national security advisor. The three foreign ministers met again on Nov. 14 on the sidelines of the APEC summit in San Francisco, where they discussed the situation in the Middle East, North Korea and Russia. On Dec. 19, South Korean Foreign Minister Park, who is returning to contest in the 2024 National Assembly elections, was replaced by Cho Tae-yul. This marked the end of a very successful run for two diplomats, Hayashi and Park, who did a lot in the past two years to repair the tumultuous relationship. But this also represents a transition point as the bilateral relationship moves into a relatively more settled, institutionalized state. 

Finally at the national security advisor level, there were strong efforts to continue coordination, including phone calls to discuss breaking events. They established a new trilateral communication hotline, enabling voice and video communication at all times, further demonstrating the closeness of the relationship. On Dec. 9, they met in Seoul for the first time since Camp David. During their meeting, they reviewed progress on trilateral initiatives, and discussed next steps for trilateral cooperation in 2024, including the supply chain early warning initiative and alignment of their respective Indo-Pacific Strategies. President Yoon hosted them for dinner a day prior and said he looked forward to continued smooth implementation of deliverables from the Camp David Summit. 

Figure 2 President Yoon Suk Yeol is pictured alongside National Security Adviser Cho Tae-yong on the left, U.S. National Security Advisor Jake Sullivan second from the left, and Japan’s National Security Secretariat Secretary General Takeo Akiba, before their dinner meeting at the presidential residence in Seoul on December 8th. Photo: Brittany Hosea-Small

Like-Minded Partners in the Making

While the pace of bilateral and trilateral diplomatic activities in the last four months of 2023 has been impressive, the new areas of cooperation may be even more important in terms of the expansion of Seoul-Tokyo-Washington partnership. These newly invigorated areas of cooperation are development and humanitarian assistance, space, cyber, and critical and emerging technology. With recent post-Camp David summit activities and the plans they have made, Japan and South Korea are serious like-minded partners in the making, shaping the contours of international affairs in the Indo-Pacific, with the United States. 

Along with their bilateral plan of establishing the Hydrogen Ammonia Global Value Chain announced in November by President Yoon and Prime Minister Kishida, Seoul and Tokyo joined Washington in reshaping international economic order through the Indo-Pacific Economic Framework for Prosperity (IPEF). On Nov. 16, the Indo-Pacific Economic Framework for Prosperity (IPEF) Leaders’ meeting brought President Biden, Prime Minister Kishida, and President Yoon together in San Francisco, based on their embrace of clean energy and global supply chain resilience. Launched in May 2022 in Japan, the 14 IPEF partners — Australia, Brunei Darussalam, Fiji, India, Indonesia, Japan, South Korea, Republic of Korea, Malaysia, New Zealand, Philippines, Singapore, Thailand, the United States, and Vietnam —  signed the IPEF Supply Chain Agreement and negotiated the Clean Economy Agreement, IPEF Fair Economy Agreement, and the Agreement of the Indo-Pacific Economic Framework for Prosperity. At the IPEF Ministerial on Nov. 13 and 14, Japanese Foreign Minister Kamikawa and Minister for Economy, Trade and Industry Nishimura Yasutoshi said that Japan will contribute approximately $10 million to the IPEF Fund designed to advance the transition to clean economy. 

The first trilateral development and humanitarian assistance policy dialogue was held in Honolulu at the end of October, which covered issues such as development financing, climate change and humanitarian assistance. This was the first deliverable from the Camp David summit to be completed. The US and Japan are top five providers of Overseas Development Assistance (ODA) in the world, while Korea is in the top 20. In their joint statement, the three partners described how they can and will use their “comparative advantages strategically to create transformational opportunities in sustainable development.” Furthermore, they identified several areas for joint cooperation in the Indo-Pacific and beyond, including in agriculture, youth entrepreneurship, healthcare, gender, as well as the Women, Peace, and Security (WPS) agenda and the Power Africa initiative. 

At the beginning of November, the three partners hosted the first trilateral dialogue on space security in Seoul. Washington has long been eager to increase space cooperation with its two largest partners in the Indo-Pacific, more urgent now against the backdrop of the rapid buildup of China’s space capabilities. Both Japan and Korea have bilaterally increased space cooperation with the US early this year, with the former signing a bilateral framework in January and the latter signing a joint statement of intent for cooperation during a visit to NASA in April by President Yoon. There has also been talks of integrating space capabilities, with both Japan and Korea keen on adding this critical new capability into the alliance. It is also important to note that US Space Forces had activated a new component field command in Korea in December 2022, making US Space Forces Korea the first field command outside the US. 

In early December, the first meeting of the trilateral working group on North Korea’s cyber threats—run by the foreign ministry—was held in Tokyo. A few weeks later, US Deputy National Security Adviser for cyber and emerging technologies Anne Neuberger went to Seoul to meet with Korean and Japanese counterparts to continue this conversation. Earlier in October, Neuberger had called North Korean hacking a “priority” for the US and pointed out the role of the trilateral partnership to tackle this problem. Overall, these meetings are an expansion of collective efforts to address the expanding North Korean threat, focusing specifically on the illicit cyber activities that fund its WMD and missile programs, including sending IT workers abroad, hacking, ransomware, and cryptocurrency theft. North Korean hackers have been prolific in the past few years, with estimates of over $340 million in 2023, and over $1.65 billion last year in stolen cryptocurrencies. 

Figure 3 After their joint press conference at the presidential office in Seoul, South Korea, National Security Adviser Cho Tae-yong of South Korea shakes hands with U.S. National Security Advisor Jake Sullivan and Japan’s National Security Secretariat Secretary-General Takeo Akiba on December 9, 2021. Photo: Chung Sung-Jun

On the issue of critical and emerging technology, Seoul, Tokyo, and Washington took a step forward by signing a trilateral framework on cooperation in science and technology in early December. US Under Secretary for Nuclear Security and NNSA Administrator Jill Hruby, Japan’s Secretary General for Science, Technology, and Innovation Policy Matsuo Hiroki, and ROK First Vice Minister and Minister of Science and ICT Cho Seong-kyung agreed that they would develop a memorandum of cooperation in early 2024 to increase scientific collaboration in these areas. This trilateral collaboration will involve US laboratories such as Los Alamos National Laboratory, Sandia National Laboratories, and Lawrence Livermore National Laboratory. 

Buttressed by “hot politics,” economic cooperation was also “hot.” There were a few noteworthy meetings. On Sept. 7, Korea and Japan held the first meeting of their heads of custom agencies in Sejong, Korea to discuss concerns surrounding cross-border crime, including drugs and sanctions-violating trade, and to create joint crackdown measures. On Dec. 1, the Bank of Korea and the Bank of Japan officially signed a three-year currency swap deal worth about $10 billion. The swap is a result of discussions held by finance ministers in June. This is the first currency swap deal between the two since the last one expired in 2015. While it is much smaller than the high of $70 billion reached in 2012, it is not an insignificant amount. Furthermore, the currency deal allows the two countries to boost their dollar liquidity and improve financial stability. 

A day later, Bang Moon Kyu, South Korea’s minister of trade, industry and energy, and Yasutoshi Nishimura, Japan’s minister of economy, trade and trade, participated in the 17th MOTIE-METI soccer exchange game in Osaka. The idea that officials from the same ministries responsible for the “white list” removals in 2019 might join a sporting event seemed unfathomable until this year. This soccer game, which hasn’t been played in five years, is more than just a game. It provided the ministers another opportunity to meet and discuss bilateral industrial, trade and energy issues, in particular the promising utilization of hydrogen. 

Aside from these channels of cooperation, other forms of cooperation thrived. Amid the volatile situation in Israel in early October, South Korea helped evacuate 51 Japanese nationals, along with 163 South Koreans and six Singaporeans aboard a military transport plane. This gesture was returned by Japan a week later, when they helped bring back 18 South Korean nationals and one foreign national family member aboard an air tanker from Israel. In early November, Japan again helped bring back 15 South Koreans and one foreign national family member, this time aboard a Japanese Air Self-Defense Force aircraft from Tel Aviv. This comes after Foreign Minister Kamikawa had pledged Japan’s “proactive” cooperation in such situations and is another display of the growing trust between the two countries. 

North Korea Threat and Defense Cooperation

In respond to North Korea’ latest provocations in late 2023, the defense ministers of Seoul, Tokyo, and Washington have tightened high-level consultations. On Sept. 7, they had a trilateral call to discuss implementation of the Camp David deliverables. They have stepped up trilateral exercises to respond to North Korean provocations. On Oct. 10, they held a two-day trilateral maritime interdiction exercise off the Korean Peninsula, the first in seven years. Prior to the exercise, senior naval commanders from each side met aboard the USS Ronald Reagan aircraft carrier, which participated in the exercise, to discuss ways to strengthen trilateral and maritime security cooperation. On Oct. 22, the three held their first-ever trilateral aerial exercises, involving US B-52 bombers and fighter jets. On Nov. 26, they conducted trilateral naval exercises in response to North Korea’s claim that its newly launched reconnaissance satellite had taken photos of US military assets in South Korea, Hawaii, and Guam. The exercise involved another US aircraft carrier, the USS Carl Vinson. Lastly on Dec. 20, right after North Korea launched the Hwasong-18 ICBM, the three conducted joint aerial drills involving B-15 bombers and fighter jets, marking the 13th time that a US bomber has been deployed to the peninsula in 2023. 

Figure 4 The Yulgok Yi I destroyer from South Korea, the US aircraft carrier USS Nimitz, and the JS Umigiri destroyer from Japan were spotted in international waters south of the southern island of Jeju. Photo: South Korea Defense Ministry

In the last four months of 2023, North Korea launched a missile on seven occasions. That’s much less compared to the last four months of 2022, when North Korea launched almost 60 missiles on 19 occasions. However, what North Korea did launch is even more concerning. On Nov. 21, it launched its first “successful” military reconnaissance satellite—reportedly with Russian technical assistance—after two failed attempts in May and August. Shortly after, it claimed to have taken satellite photos of the White House, the Pentagon and US aircraft carriers at Naval Station Norfolk, as well as Guam, South Korea, Italy, and Washington. 

Figure 5 The North Korean government provided this photo, claiming it depicts the launch of the Malligyong-1 military spy satellite into orbit on Tuesday, November 21, 2023. Photo: Korean Central News Agency/Korea News Service

None of the imagery has been confirmed since North Korea has yet to release any pictures publicly. There has also been no independent corroboration of North Korea’s claims that its satellite is fully functioning and in communication. While one has to take North Korea’s words with a grain of salt, the fact that it succeeded in launching a satellite safely into orbit means that it has made another technological leap forward. Furthermore, North Korea accomplished this even before South Korea successfully launched its first military reconnaissance satellite, which came 10 days later on Dec. 1. Most importantly, North Korea had told the world it would not stop with just one satellite in space. It ended 2023 with a vow to launch three more satellites in 2024. 

The biggest show in the expansion of trust in the bilateral and trilateral security cooperation came on Dec. 19, when the long-awaited real-time North Korea missile warning data sharing mechanism was activated. The missile sharing data was used to track the Hwasong-18 ICBM launched by North Korea that day. Based on the flight data collected, South Korea and Japan deduced the ICBM had the range to hit anywhere in the continental US. Activating this mechanism is a major marker of trust for the relationship, given the fraught bilateral history of another similar agreement, GSOMIA (the General Security of Military Information Agreement). They also announced the establishment of a multi-year trilateral exercise plan beginning in 2024. This guarantees that cooperation is on the calendar for the next couple of years, giving the relationship stability and sending the message to competitors and adversaries that the trilateral is here to stay. 

Troubling Domestic Politics for Kishida and Yoon

For their crucial role in this historic achievement and rapprochement, South Korean President Yoon and Japanese Prime Minister Kishida were awarded a Profile in Courage Award by the John F. Kennedy Library Foundation in October 2023. They were recognized for having tackling the hardest political problem head on, and more tellingly, early into their respective time in office. But the critical question is how to make this momentum last. Domestic politics—1) public opinions and 2) approval ratings—holds the key. 

Public opinions are an important factor that can impact and shape the future of Seoul-Tokyo bilateral ties. How has a breakthrough in bilateral relations in 2023 affected Japanese and South Korean public perceptions? According to the annual joint public opinion surveys conducted in August and September by South Korea’s East Asia Institute (EAI) and Japan’s Genron NPO, both Japanese and South Koreans said that the bilateral relations improved in 2023. In 2022, 64.6% of South Koreans felt that the relations were negative. In 2023, the number went down to 42%. In Japan, 21.2% of respondents answered that the relations were negative in 2023, compared to 39.8% in 2022. In 2023, 12.7% of South Korean and 29% of Japanese respondents felt that Japan-South Korea relations were “very good.”

Importantly, the same EAI-Genron NPO survey results indicate that despite the improvement of Seoul-Tokyo relations, South Koreans’ favorability toward Japan has not improved, which slightly decreased from 30.6% in 2022 to 28.9% in 2023. The percentage of Japanese respondents’ favorable impression of South Korea, however, improved from 30.4% in 2022 to 37.4% in 2023. Genron NPO notes, “the most commonly selected answer among South Korean respondents for the reasons for their poor impression of Japan (at 65.4%) was that they believe Japan has not properly reflected on its history in regard to its invasion of the Korean peninsula.” Based on an ordinal logistic regression analysis, the EAI Issue Briefing states, “even if the South Korean government makes proactive efforts, it may be difficult to improve South Korean favorability toward Japan if the Japanese government does not respond positively and takes a passive stance.” Their analysis confirms that how people in both countries evaluate their own and the other governments’ policies affect their feelings about each other and about bilateral relations. More Japanese supported the efforts of both the South Korean and Japanese governments at 34.8% and 34. 5%, respectively; 21.7% of South Koreans evaluated their own government’s efforts positively, while 15% evaluated Japan’s efforts positively.

Amid low approval ratings of Yoon and the ruling People Power Party (PPP), President Yoon replaced about a third of his ministers in December, which marked the biggest in scale since the beginning of his tenure as president. Cho Tae-yul, formerly a second vice foreign minister and ambassador to the United Nations, was appointed foreign minister, replacing Park Jin; Cho Tae-yong would be new National Intelligence Service Director, a former national security advisor. On Jan. 1, 2024, Chang Ho-jin assumed the role of National Security Office chief. One of the biggest questions is the general election in April 2024. There are many moving parts. The main opposition party leader Lee Jae-myung (whose non-fatal knife attack took place after the reporting period but before publication) is dealing with scandals; key political figures—Lee Nak-yon from the liberal camp and Lee Jun-seok from the conservative camp—have announced their intentions to leave the Democratic Party of Korea (DPK) and the PPP, respectively, and create their own new parties; popular Justice Minister Han Dong-hoon resigned from his position and assumed the post of PPP interim chief in preparations for the April election. 

Similarly, on Dec. 14 a political funds scandal prompted Prime Minister Kishida to replace all four ministers who are part of the political faction previously led by Abe in the Liberal Democratic Party (LDP). After some rebound in the approval rating over his foreign policy performance, in the final months of 2023, Kishida’s Cabinet approval ratings were dropping. According to a Asahi Shimbun survey, they were 29% in November, a fall from 37% in September. In addition to the public’s lukewarm support for Kishida’s economic package, Asahi’s December survey suggests that Kishida’s handling of the LDP’s fundraising scandal was not received well. 58% of respondents said that they want Kishida to resign as prime minister. 78% of respondents said that the LDP cannot change the way it works in terms of money in politics, while 16% said that the party can reform itself. Around the same time, a Jiji Press poll showed that the public approval rating of Kishida’s Cabinet sank to a record low at 17.1%, down 4.2% from November. 

Looking Ahead

What do this year’s developments tell us about 2024? Will the current momentum sustain? We have mixed signs. On the one hand, there have been unprecedented efforts toward the institutionalization of bilateral and trilateral cooperation, which will help. On the other hand, domestic politics circumstances of both Japan and South Korea do not bode well. Kishida and Yoon—the two leaders at the heart of blossoming of cooperation—have been struggling for popularity among voters. Importantly, a recent public opinion survey tells us that despite the improvement of South Korea’s relations with Japan, South Korean public perceptions toward Japan have not improved. 

In 2024, the three partners will serve together on the United Nations Security Council (UNSC), with Japan and South Korea joining as elected nonpermanent members. With important elections on the horizon, and whatever the trouble they might have at home, these three partners will likely continue to be eager participants of global affairs together.