IGCC Postdoc Jung Jae Kwon Talks War, Peace, and Nukes

You conduct research on nuclear weapons, the bread‑and‑butter of the IGCC postdoctoral fellowship. What first motivated you to get into this space?

When I first started my PhD, I wasn’t initially interested in nuclear weapons. But—as a bit of background, although I’ve been in Boston half of my life, I’m originally from South Korea—and my graduate studies began during the fire-and-fury period of nuclear saber-rattling between President Trump and North Korean leader Kim Jong‑un. So, at that formative time, nuclear issues became highly salient for me and I gravitated toward studying nuclear weapons and the international politics surrounding them. It also happened that I started working with my doctoral advisor at the Massachusetts Institute of Technology (MIT), Vipin Narang, a leading nuclear expert. So there was a convergence of many factors.

We often hear that nuclear weapons seem remote to most people, but for you it sounds like the opposite, being from South Korea.

Yes, that’s right. The Trump‑Kim drama made the dangers seem very real. South Koreans know they are surrounded by three nuclear powers—North Korea, China, and Russia—and the United States is also nearby. We’re right in the middle of four nuclear states, without possessing nuclear weapons ourselves.

Nuclear weapons therefore loom large in the South Korean discourse. Knowing that, I was motivated to write a dissertation on the alliance politics of nuclear deterrence. That has a lot of relevance for South Koreans—can we be kept safe when we don’t have any of our own nuclear weapons? How effectively can we rely on our ally, the United States, to deter others on our behalf while doing what we can to shore up deterrence?

And what did you initially focus on in undergrad?

At Harvard, I studied international relations broadly. I had many interests, but international security became my primary focus.

The primary reason for that was my military service with the Republic of Korea Army. Like most South Korean men, I completed two years of service after my sophomore year. I was deployed to South Sudan on a United Nations peacekeeping mission. Two months in, a civil war erupted, giving me a first‑hand view of conflict.

My experience of the South Sudanese civil war sparked my interest in war and peace. When I returned to Harvard, I resolved to study international security more seriously.

That must have been intense. How did your experience in South Sudan shaped who you are?

It brought me out of my comfort zone and gave me more purpose in my studies.

I arrived in South Sudan with little knowledge of the country. The first months felt almost like a safari, relatively peaceful and relaxed. But after a time, the first signs of fissures in South Sudanese leadership emerged, with an ethnic component to the division. Within days the country devolved into civil war, and international organizations warned of a Rwanda‑style genocide.

I was a Harvard undergrad—privileged and accustomed to the comforts of the United States—suddenly confronted with extreme violence and a massive humanitarian crisis unfolding. That stark contrast made me determined to conduct serious research on the roots of the sort of violence and destruction I saw in South Sudan.

Since then, I’ve gravitated more towards studying conventional military strategy and nuclear deterrence.

What attracted you to the IGCC fellowship, and how do you see it shaping your career?

My goal has always been to produce rigorous research that informs contemporary policy debates. IGCC is an ideal place to do that because the fellowship is located in D.C., affiliated with the National Labs, and offers access to a community of political scientists, technical experts, and policy practitioners.

I love talking to policymakers, military officers, and technical experts for my research. The IGCC network felt like one where I could both fit in and grow intellectually. I’m excited to live in D.C., engage with nuclear security experts, and broaden my knowledge beyond nuclear issues to other technologies.

What have you liked about living in D.C. so far?

Until now, my time in the U.S. has been limited to Massachusetts. I’m delighted to be experiencing a new city, and have spent my time exploring D.C.’s architecture, neighborhoods, and museums—although I came right in time for the government shutdown to close them all [laughs].

I’m also a big baseball fan, so I recently went to watch a Washington Nationals game.  Not surprisingly, they lost. The fans around me found out I was new to town and immediately started complaining about how the Nationals have been “rebuilding” for years.

What will you miss most about Massachusetts?

The cold winters and snow, obviously [laughs].

But seriously, I’ll really miss the vibrant academic environment—Boston’s many schools, Cambridge’s concentration of students, and the community of young intellectuals working passionately on their research projects.

I want to ask more about your own passion project. You study the interplay between conventional and nuclear strategy, particularly how nonnuclear allies can influence deterrence. Could you speak to that from a South Korean perspective?

U.S. allies like South Korea without their own nuclear arsenals are fundamentally limited in their actions, because they rely on the U.S. nuclear umbrella for security against nuclear‑armed adversaries.

My dissertation—and the book project it will become—examines how such allies try to exercise agency within those constraints. I look at not only South Korea, but also Japan, West Germany, and Norway, to find commonalities and differences in how these countries work to counter threats from nuclear neighbors in partnership with the United States.

South Korea is unique because its conventional military posture is explicitly aimed at North Korea’s nuclear forces, and it seeks to deter a North Korean nuclear attack partially through its conventional means. No other country, to my knowledge, employs such a strategy. It’s risky and could generate escalation dynamics in a crisis situation. But Seoul has chosen to leverage its advanced conventional capabilities and embrace that risk under the protection of the U.S. nuclear umbrella.

Is the South Korean case unique, or can other nonnuclear states learn from Seoul?

South Korea’s case is largely unique. Its aggressive conventional posture against a nuclear‑armed neighbor is not something European states can replicate against Russia, given the risks, power disparity, and the geography. Israel—although it has nuclear weapons—has a somewhat similar conventional military strategy to South Korea, but it does not face a nuclear‑armed adversary.

Generally, nonnuclear allies are limited in how they can bolster deterrence, but South Korea’s heavy investment in conventional forces gives it some agency.

You studied in China. What did that experience teach you about the country?

I completed a master’s at Peking University in Beijing. I feel like I caught the last wave of U.S.-China academic cooperation before the pandemic and the increase in geopolitical tensions effectively halted these exchanges.

Being a South Korean in China with a degree from the U.S. gave me a unique perspective. I traveled widely. At the time, I observed that Chinese policymakers were intent on “catching up” with the rest of the world in economic, military, and technological domains. I felt there was a sense within China that many aspects of its society were still backward compared with advanced economies, and there was a strong drive to modernize.

Since then, China has become more confident—economically, politically, and militarily. It is now locked in an intensified great power competition with the United States across all domains. And it is not shying away.

What was the most memorable place you visited in China?

I toured many different parts of China, but the most interesting spot for me was the China‑North Korea border.

As a Korean speaker, I could communicate with ethnic Koreans there and see how China remembers its involvement in the Korean War. I also saw the stark contrast between China’s development and the backwardness of North Korea across the river.

What are your plans for the fellowship?

I’ll spend most of my time revising my manuscript and working on a couple of article projects that stem from my dissertation. I plan to present these at IGCC and other conferences. I also want to engage with the expert community based in the D.C. area.

Overall, I aim to produce research that is both academically rigorous and relevant to contemporary policy debates, leveraging the unique community and resources that IGCC and D.C. offer.