The End of East Asian Pacifism: Nuclear Policy in Japan and South Korea

Aaron Pultman and Sarah Rosenberg

Executive Summary

North Korea’s nuclear arsenal poses a monumental threat to its neighbors throughout Asia. South Korea and Japan, however, are in particular danger due to their proximity to the rogue nation and their ties to the United States. There are numerous possible solutions to resolve this danger, yet they vary in their efficacy, feasibility, and practicality. Two specific possibilities stand out from previous literature on the subject: Japan and South Korea can develop their own nuclear arsenals, or maintain the status quo by relying on the U.S. nuclear umbrella. Both of these strategies carry just as many drawbacks as positive aspects, including cost and effectiveness. We propose a different solution: the deployment of U.S. nuclear weapons to Japan and Korea. This solution rates the highest in its practicality and capability to truly deter North Korean aggression. We use speeches, polls, and articles to demonstrate that this solution would be met with favor in the two countries. This strategy will provide the region with a stable measure to counter North Korean nuclear hostility and maintain peace.


            There are numerous security threats currently facing Asia, ranging from China’s desire to achieve hegemony in the region, Russia’s coziness with strongmen in the area like Xi Jinping, and, most significantly, North Korea’s nuclear weapons program. This rogue state has repeatedly demonstrated its nuclear capability and its constantly improving ballistic missile technology. Both Japan and South Korea lie in geographic proximity to North Korea, leaving them exposed to a variety of conflicts with the latter. Additionally, Japan and South Korea are both steadfast allies of the U.S. Consequently, tension between the U.S. and North Korea could also affect Japan and South Korea. Finally, conflict has occurred in the past and, given North Korea’s recent aggressive posture, it is a distinct possibility. One option for responding to the threat is through Japanese and Korean nuclear weapons. This paper seeks to answer the question of what, if any, nuclear measures should Japan and South Korea attempt.

Literature Review

Many scholars argue against the Japanese and Korean acquisition of nuclear weapons. Earlier literature focuses on China as the primary threat given its desire to attain regional hegemony. In addition, there was apprehension that if the Sino-American relationship improved, Tokyo and Seoul would feel isolated.[1] Some policy officials worry whether a cascade effect could occur if either country attained nuclear weapons; it could open the door for countries like Myanmar, Vietnam, Taiwan, and Australia to create their own programs out of fear of North Korea.[2] Lee Choon-geun of the Korean Institute for International Economic Policy claims that if South Korea obtained nuclear weapons, Japan would undoubtedly follow.[3] As such, if China wants to avoid this cascade in order to maintain its hegemonic position, it would be in its interest to convince Pyongyang to abandon its nuclear weapons program. Notably, this stance aligns with that of the U.S. and the international community.[4]

With South Korea specifically, most scholarship focuses on developing a stronger relationship with the North and rolling back their nuclear program. Prominent national figures such as former President Park Geun-hye, have argued for trust building between the two countries in the past.[5] This perspective is maintained by numerous scholars and policymakers despite the ultimate failure of South Korea’s Sunshine Policy[6]. The biggest factor for many scholars is whether the U.S. can guarantee the security of South Korea given its proximity to the North.[7] There exists, however, contradicting opinions whether the U.S. can do so, particularly given its robust trade relationship with China, Pyongyang’s biggest ally. It is notable that the majority of scholarship on the South Korean nuclear question was primarily written in the early 2000s, as most modern academic literature focuses on the role of China as a mediator and the possibility of Japanese acquisition of nuclear weapons.

This question of nuclearization of Japan and South Korea is particularly pertinent given the current regional dynamics. Opinion remains divided both in the academic community and among policymakers, with particularly stark differences between public opinion in these two countries. Many, however, focus on whether Japan and South Korea should manufacture their own nuclear weapons or merely strengthen the U.S. nuclear umbrella. Instead, both countries should consider stationing U.S. nuclear weapons on their soil in order to more effectively deter North Korea. U.S. security guarantees have failed to slow North Korea’s nuclear program; therefore new measures should be taken.

Analysis & Discussion

Given the importance of the Korean and Japanese governments’ official stance on the issue, documents from the Prime Minister’s or President’s office, the Ministry of Foreign Affairs, the Ministry of Defense, and other related government institutions proved to be particularly valuable. In addition, documents from international organizations like the United Nations are relevant given Japan’s leadership in nonproliferation efforts. To gain a scholarly view on the subject, defense and international relations journals provided various literature, demonstrating how the academic world believed the issue could be solved. Finally, English newspapers in Japan and South Korea contributed information on the media and broader public’s view through reporting, polls, and editorials.

In Japan, members of the Liberal Democratic Party are more open to the idea of nuclear weapons. Despite Japan’s three non-nuclear principles — no possessing, manufacturing, or allowing nuclear weapons on its territory – some LDP officials propose reinterpreting the Constitution to permit some form of nuclear protection. Former LDP Defense Minister Shigeru Ishiba suggested allowing U.S. nuclear weapons on Japanese soil to deter North Korea, though he condemned manufacturing their own weapons.[8] This position is still highly controversial in Japan: recent numbers show that fewer than one in ten Japanese citizens support nuclear armament, yet the LDP has continued to win elections.[9]

Most recently, Prime Minister Shinzo Abe received a stronger mandate after calling for snap elections in October 2017.[10] While LDP policies extend beyond North Korea, Abe campaigned on building up the Japanese military and revising Article 9.[11] With the new elections, Abe obtained the necessary majority to do so and plans to rewrite the constitution by 2020.[12] Despite the lack of popular support among Japanese citizens, they would likely be more inclined to accept nuclear armament if South Korea did so first. When discussing a nuclearized Japan and South Korea, many scholars speak of both acquiring nuclear weapons rather than simply one country. If the security situation becomes dire enough, Japan will have little choice but to allow nuclear weapons on its territory.

Japan and the U.S. cooperate closely on security, but as early as 2012 the LDP recognized Japan must do more to protect itself. When the opposition party, the Democratic Party of Japan, lost to LDP in 2012, the ruling government issued a new National Defense Program Guidelines (NDPG). It expressed the need to maintain and strengthen ballistic missile defense, in particular, to address the threat of nuclear weapons. The document explicitly mentions North Korea, China, and Russia as posing the greatest risks to Japanese security, though the government recognized that the likelihood of conflict remained low at that time.[13] While the NDPG states that Japan will play a “rigorous and active role in nuclear disarmament and non-proliferation efforts,” it also recognizes that Japanese defense must be constantly reevaluated to ensure it is meeting the necessities of the current security environment.[14] Given North Korea’s recent antagonistic behavior, Abe will likely try to expedite the process of redefining Japan’s pacifist constitution in order to comply with the NDPG’s directive of changing defense to meet the security conditions.

Many in the international community have expressed concerns over Japan’s new defensive attitude, particularly at the UN. Every year, Japan submits a resolution to the UN General Assembly on nonproliferation and the elimination of nuclear weapons. This year, however, delegates expressed apprehension about the wording of the resolution, raising the possibility that Japan watered down the language in order to justify the potential use of nuclear weapons.[15] Japanese officials claim, however, that they faced pressure from the U.S. to make this change.[16] In the text of the resolution, rather than acknowledging “the catastrophic humanitarian consequences of any use of nuclear weapons,” the new resolution says, “the catastrophic humanitarian consequences of nuclear weapon use.”[17] This small change in language contains drastic implications for Japan’s efforts in fighting North Korea because it no longer excludes the use of nuclear weapons against the regime. The resolution demonstrates that Japan is willing to risk its international image as the leader of the nonproliferation movement in order to counter North Korea. Perhaps the next step is to adjust its nuclear policy.

            In South Korea, the debate over a nuclear counter to the North dominates politics. With just under two hundred kilometers between Seoul and Pyongyang, South Korea has always sought ways to deter the threat from North Korea, yet early efforts primarily focused on nonproliferation. South Korea had a nuclear weapons program in the 1970s, but the U.S. forced the government to abandon the project.[18] In 1991, President Roh Tae Woo said that South Korea would not, “manufacture, possess, store, deploy, or use nuclear weapons.”[19] Only two months later, North and South Korea signed the Joint Declaration of the Denuclearization of the Korean Peninsula. In this agreement, both sides pledged not to “test, produce, receive, possess, store, deploy or use nuclear weapons; to use nuclear energy only for peaceful purposes; and not to possess facilities for nuclear reprocessing or uranium enrichment.”[20] Implementation of the agreement’s inspection regime stalled in 1993 due to revelations about the North Korean nuclear program. Despite this setback, South Korea has not renounced its obligations under the treaty.[21] Given the North’s recent escalations of nuclear testing, attitudes towards Seoul’s obligation to the treaty are beginning to change.

While for decades it seemed unthinkable, Korean opinions on nuclear weapons have recently begun to shift. A poll conducted by Gallup Korea found that 60% of Koreans support nuclear weapons for their country.[22] Woo Yoo-chul, a senior figure in the then-ruling Saenuri Party, suggested last year that Korea should develop “peaceful” nuclear weapons to counter the North.[23] This recommendation is in part caused by a lack of faith in the continuing efficacy of the U.S. nuclear umbrella under President Trump. These concerns created broader support for a different proposal: the redeployment of American nuclear weapons to South Korea.

For many years, the U.S. maintained an arsenal of nearly one hundred nuclear weapons in South Korea. In 1991, however, President George H.W. Bush withdrew them under the condition that Moscow withdrew its own weapons from the Peninsula as well.[24] Recently, there has been a major push to bring the weapons back. A poll by YTN, a Korean cable news company, found that 68% of Koreans supported the redeployment of U.S. nuclear weapons.[25] Several months ago, Korean Defense Minister Song Young-moo said that redeployment was an idea worth reviewing.[26] President Moon Jae-in has publicly opposed the idea while the opposition Liberty Korea Party strongly argues for redeployment.[27] These varying political positions demonstrate the gap between public officials’ opinions and the general public.

One of the obstacles that Japan and South Korea must overcome in deterring North Korea is the risk of international condemnation. Both countries signed the Nuclear Non-Proliferation Treaty and would risk sanctions if they violated its terms or withdrew. Although the international community may be reluctant to sanction two of the world’s largest economies, it would still cause international outrage and undermine the NPT.[28] Some nuclear weapons experts, however, argue that the treaty has been a failure for Asian democracies; thus these countries should not adhere to it. While Japan’s pacifist constitution is expected, it is no longer sustainable with the threats from North Korea.[29] Its acquisition or stationing of U.S. nuclear weapons may seem symbolic, but realistically neither Japan nor South Korea are aggressive powers. These proposals should not be taken lightly, but one should also be pragmatic about the security situation. In addition, the election of President Trump has complicated matters given his statements that he would not object to either country obtaining nuclear weapons.[30] It is unclear whether or not he will make policy based on that assertion, but it is likely that he would take a more favorable position to aggressive nuclear policies in both Japan and South Korea.


Under the current security situation, Japan and South Korea must seriously consider reevaluating their nuclear policies. Both governments are undergoing that process, though the Korean situation may change under Moon Jae-in. Rather than creating their own programs, stationing U.S. nuclear weapons would be the most effective way to deter North Korea. The world does not need more nuclear weapons, and deploying U.S. weapons instead would ensure security while not condoning increased proliferation. This move is unlikely to lead to a cascade effect, as Japan and South Korea are most threatened by North Korea, and other countries will feel more secure with weapons. Despite the stigma of this decision, current policies have failed; these countries must change their positions or face the threat of nuclear annihilation.

The Asahi Shimbun (Tokyo, Japan). “Ex-defense chief Ishiba suggests change in anti-nuke

policy.” September 7, 2017.

Chan, Melissa. “Here’s What Donald Trump Has Said About Nuclear Weapons.” Time. August 3,


Corrs, Anders. “Japan: Go Nuclear Now.” Forbes. February 1, 2017.

Geun-hye, Park. “A New Kind of Korea: Building Trust Between Seoul and Pyongyang.”

Foreign Affairs 90, no. 5 (September/October 2011).

Government of Japan. “Defense National Program Guidelines.” December 17, 2013.

Fifield, Anna. “South Korea’s defense minister suggests bringing back tactical U.S. nuclear

weapons.” The Washington Post. September 4, 2017.

The Japan Times (Tokyo, Japan). “An idea buds in the U.S. that Japan should go nuclear.”

October 24, 2017.

Kojo, Hirotaka. “40,000 protest Abe’s plans to revise Article 9 of Constitution.” The Asahi

Shimbun (Tokyo, Japan), November 4, 2017.

Lee, Dennis. “A Nuclear Japan: The Push for Weaponization.” Harvard International Review 35, 1 (Summer 2013).

Lee, Michelle Ye Hee. “More than ever, South Koreans want their own nuclear weapons.” The

Washington Post. September 13, 2017.

O’Neil, Andrew. “Extended nuclear deterrence in East Asia: redundant or resurgent?”

International Affairs 87, no. 6 (November 2011).

Osaki, Tomohiro. “Abe claims victory as powerful endorsement, may seek re-election next

month.” The Japan Times (Tokyo, Japan), October 23, 2017.

Ota, Masakatsu. “Japan waters down text of annual anti-nuclear resolution to imply acceptable

use of nukes.” The Japan Times (Tokyo, Japan), October 21, 2017.

Park, Ju-min. “Calls in South Korea for nuclear weapons as parliamentary poll looms.” Reuters.

February 15, 2016.

Sanger, David, Choe Sang-Hun, and Motoko Rich. “North Korea Rouses Neighbors to

Reconsider Nuclear Weapons.” The New York Times. October 28, 2017.

“South Korea.” Nuclear Threat Initiative. December 2015.

UN General Assembly. “Approving 18 Drafts on Disarmament Measures, First Committee Urges

General Assembly Call for States to Sign Nuclear-Weapon-Ban Treaty.” News release. October 27, 2017.

UN General Assembly, Draft Resolution L.35, “General and complete disarmament: United

action with renewed determination towards the total elimination of nuclear weapons,” October 12, 2017.

Woo, Roh Tae. “President Roh Tae Woo’s Declaration of Non-Nuclear Korean Peninsula Peace

Initiatives.” Federation of Atomic Scientists. November 8, 1991.

[1] Dennis Lee, “A Nuclear Japan: The Push for Weaponization,” Harvard International Review 35, no. 1 (Summer 2013): 8,

[2] David Sanger, Choe Sang-Hun, and Motoko Rich, “North Korea Rouses Neighbors to Reconsider Nuclear Weapons,” The New York Times, October 28, 2017,

[3] “An idea buds in the U.S. that Japan should go nuclear,” The Japan Times (Tokyo, Japan), October 24, 2017,

[4] Ibid.

[5] Park Geun-hye, “A New Kind of Korea: Building Trust Between Seoul and Pyongyang,” Foreign Affairs 90, no. 5 (September/October 2011): 14,

[6] The Sunshine Policy was the name given to South Korea’s foreign policy stance towards the North from 1998 to 2008. It entailed greater communication with and economic aid to North Korea.

[7] Andrew O’Neil, “Extended nuclear deterrence in East Asia: redundant or resurgent?,” International Affairs 87, no. 6 (November 2011): 1439,

[8] “Ex-defense chief Ishiba suggests change in anti-nuke policy,” The Asahi Shimbun (Tokyo, Japan), September 7, 2017,

[9] Sanger, Sang-Hun, and Rich, “North Korea Rouses.”

[10] Tomohiro Osaki, “Abe claims victory as powerful endorsement, may seek re-election next month,” The Japan Times (Tokyo, Japan), October 23, 2017,

[11] Hirotaka Kojo, “40,000 protest Abe’s plans to revise Article 9 of Constitution,” The Asahi Shimbun (Tokyo, Japan), November 4, 2017,

[12] Osaki, “Abe claims.”

[13] Government of Japan, “Defense National Program Guidelines,” December 17, 2013,

[14] Ibid.

[15] UN General Assembly, “Approving 18 Drafts on Disarmament Measures, First Committee Urges General Assembly Call for States to Sign Nuclear-Weapon-Ban Treaty,” press release, October 27, 2017,

[16] Masakatsu Ota, “Japan waters down text of annual anti-nuclear resolution to imply acceptable use of nukes,” The Japan Times (Tokyo, Japan), October 21, 2017,

[17] UN General Assembly, Draft Resolution L.35, “General and complete disarmament: United action with renewed determination towards the total elimination of nuclear weapons,” October 12, 2017.

[18] “South Korea,” Nuclear Threat Initiative, December 2015,

[19] Roh Tae Woo, “President Roh Tae Woo’s Declaration of Non-Nuclear Korean Peninsula Peace Initiatives,” Federation of Atomic Scientists, November 8, 1991.

[20] Ibid.

[21] Ibid.

[22] Michelle Ye Hee Lee, “More than ever, South Koreans want their own nuclear weapons,” The Washington Post, September 13, 2017,

[23] Ju-min Park, “Calls in South Korea for nuclear weapons as parliamentary poll looms,” Reuters, February 15, 2016,

[24] Anna Fifield, “South Korea’s defense minister suggests bringing back tactical U.S. nuclear weapons,” The Washington Post, September 4, 2017,

[25] Ibid.

[26] Ibid.

[27] Ibid.

[28] Sanger, Sang-Hun, and Rich, “North Korea Rouses.”

[29] Anders Corrs, “Japan: Go Nuclear Now,” Forbes, February 1, 2017,

[30] Melissa Chan, “Here’s What Donald Trump Has Said About Nuclear Weapons,” Time, August 3, 2016,