Japan and South Korea: Will History Repeat or Reform?

Japan and South Korea marked the 60th anniversary of diplomatic normalization on June 22. Over the past six decades, their bilateral relations have swung between episodes of reconciliation and turmoil.

Now, with a new progressive government in Seoul, fresh uncertainty looms. President Lee Jae-myung, who took office on June 4, comes with no prior foreign policy experience and carries a record of harsh rhetoric toward Tokyo.

Lew Seok-choon, a sociologist and retired professor of Yonsei University, says a lasting friendship requires an honest reckoning with shared history and steady civilian engagement.

In an interview with JAPAN Forward, Lew reflected on six decades of diplomatic turbulence, shifting regional dynamics, and South Korea's path forward under its new leadership.

Lee Jae-myung's Dilemma

How do you assess Japan and South Korea's relations up to now?

Following years of arduous negotiations, South Korea and Japan normalized their relations on June 22, 1965. Their leaders at the time were President Park Chung-hee and Prime Minister Eisaku Sato. Despite facing public opposition at home, Park's government maintained relatively stable bilateral ties with Tokyo throughout his presidency, relying on shared cultural affinities and economic cooperation.

*PM Shigeru Ishiba delivers remarks at a Japan–South Korea diplomatic normalization event in Tokyo, June 19. (Prime Minister's Office)*

In the 1980s, during President Chun Doo-hwan's administration, this trend appeared to persist. However, Japan's first major textbook controversy in 1982 prompted Seoul to more actively leverage historical issues as diplomatic tools. By the early 1990s, the comfort women issue had emerged as another significant source of tension between the two countries.

Beyond that point, historical grievances have consistently been brandished as a diplomatic card to varying degrees. This reached its peak under the Moon Jae In administration, when bilateral relations hit a nadir. Relations then recovered markedly under Moon's successor, Yoon Suk-yeol. Yet with a staunchly leftist government returning to power, the future of Tokyo-Seoul relations remains on shaky grounds.

South Korean President Moon Jae-In is welcomed by Japanese Prime Minister Shinzo Abe upon his arrival for a welcome and family photo session at the G20 leaders summit in Osaka, Japan, June 28, 2019. REUTERS/Kim Kyung-Hoon/Pool

Would policies toward Japan change under Lee Jae-myung?

Many in Japan are aware that Lee has historically taken an openly combative stance toward Tokyo. During his recent presidential campaign, however, he softened his tone, advocating for a more robust ties. This shift was evident during Lee's first meeting with Japan's Prime Minister Shigeru Ishiba on the sidelines of the G7 summit in June.

*Prime Minister Shigeru Ishiba and South Korean President Lee Jae-myung meet on the sidelines of the G7 Summit in Canada. (©Prime Minister's Office)*

I don't see Lee as being as ideologically rigid as Moon. Many describe him as a pragmatist — someone willing to do whatever it takes to ensure political survival. I largely agree with this view. In that sense, as long as South Korea's interests and his own political position aren't threatened, he has little reason to damage relations with Japan. To that end, there is a genuine possibility that Lee and Ishiba could find common ground.

The main challenge for Lee lies in his core base, which remains stubbornly left-wing and deeply skeptical of Japan. Lee, of course, has been openly critical of his predecessor's conciliatory approach toward Tokyo. If the new president were to inherit and continue those policies, widespread unrest among liberal constituents could ensue, with major consequences for Lee.

Will Lee follow through on his anti-Japan rhetoric?

Lee could pivot to a more anti-Japan stance if his approval ratings drop or if he faces domestic policy setbacks. But one crucial factor to consider is the "Trump element." Donald Trump's second term signals a much tougher approach toward China.

Lee, then head of the Democratic Party, meets with Chinese Ambassador Xing Haiming in June 2023. The meeting drew criticism over what some viewed as Lee's excessive deference to Beijing. (©National Assembly Press Team)

Given Lee's known pro-Beijing leanings, any move to sideline Japan and the United States in favor of closer ties with China would likely taint relations with Washington. In light of recent American strikes on Iranian nuclear sites, we now have a clearer sense of what an America First foreign policy entails. Moving forward, South Korea will need to navigate its diplomatic and security policies with great care and vigilance.

A Time for True Reconciliation

Can Lee replicate the approach of the Roh Moo-hyun era?

Roh, of course, was a distinctly left-leaning South Korean president who served from 2003 to 2008. While his foreign policies had considerable flaws, he managed to push through several measures that faced strong opposition from his supporters.

*President George W. Bush welcomes President Roh Moo-hyun of South Korea to the Oval Office on Thursday, Sept. 14, 2006. (©White House)*

In 2007, for instance, he successfully signed a free trade agreement with the US, despite facing serious pushback from his core supporters. A good portion of them worked in the agricultural sector, which was expected to face fierce competition from cheaper American imports.

Another example is Roh's decision to deploy South Korean troops to the Iraq War. While he was generally viewed as lukewarm toward Washington, Roh recognized the strategic importance of the traditional alliance. Whether Lee can demonstrate the same level of resolve remains to be seen. Personally, I don't think the current president has the same degree of conviction or charisma to pull it off.

You said that Lee might crack down on pro-Japan speech at home. Can you elaborate?

A law amended under the Moon administration criminalizes the spread of false information on the 1980 Gwangju Uprising. One scholar has already been jailed over his research. Similar attempts to penalize challenges to mainstream colonial-era narratives were introduced but ultimately failed.

*Lew Seok-choon and Tsutomu Nishioka discuss Japan-South Korea relations at a HARC forum in Tokyo, June 21. (©Kenji Yoshida)*

Under Lee, we may see renewed efforts by the left-wing dominated legislature to revive such measures. By regulating speech at home, Lee could aim to suppress pro-Japan views domestically without directly provoking Tokyo.

Are there any positive prospects for the bilateral relationship?

There has been a noticeable shift in South Korean public sentiment toward Japan. A recent report by the Asan Institute for Policy Studies highlights that young people in their 20s have maintained a consistently favorable view of Japan since the Moon Jae In era. Even more significant is the gradual uptick in positive sentiment among individuals in their 60s, a generation that has traditionally been more anti-Japanese.

This year, a record number of South Koreans visited Japan, and vice versa. What truly matters are these people-to-people exchanges, not politics. Governments change, and even the best policies don't always stick. For an enduring partnership, both sides, especially South Korea, must honestly confront their past and build a shared understanding rooted in mutual respect.