Japan’s potential assistance in South Korea’s nuclear deterrence and defense

Abstract

As North Korea emphasized its “second mission,” the reunification of the two Koreas, with its nuclear weapons, South Korea has been mobilizing all potential resources to deter North Korea’s attempt. Indeed, it rapidly improved its relations with Japan as well as strengthened the U.S. extended deterrence through the “Washington Declaration” in early 2023. The United States, South Korea, and Japan even initiated their trilateral summit meeting to discuss their combined deterrence posture against North Korea. This article evaluates South Korea’s current nuclear preparedness, including preemptive/preventive strikes, missile defense, and civil defense, identifies weaknesses, and analyzes whether Japan can mitigate the weakness.

Disclosure statement

In accordance with my ethical obligation as a researcher, I am reporting that I do not receive any funding from a company that may be affected by the research reported in the enclosed paper. I have disclosed those interests fully, and I have in place an approved plan for managing any potential conflicts arising from that involvement.

Notes

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Additional information

Notes on contributors

Hwee-rhak Park

Dr. Hwee-rhak Park ([email protected]) is a visiting professor of the University of the Philippines, the Philippines. Before this, he retired as a professor from Kookmin University, Seoul in August 2021. Even after his retirement, he continued to conduct research as a visiting scholar at the Center for Strategic Studies at the Fletcher School of Law and Diplomacy, Tufts University, Boston, from September 2021 to July 2022. During his time at the Fletcher School, he published three articles in international journals in 2022, namely "North Korea’s Nuclear Armament Strategy and Deception" in Defense Studies, "Investigating Nuclear-Armed North Korea’s ‘Strategic’ Challenge and Options for the United States and South Korea" in International Area Studies Review, and "An Investigation into North Korea’s ‘Real’ Nuclear Strategy: A Comparison with Pakistan’s Case" in the Journal of Asian Security and International Affairs. In 2023, Dr. Park published two English articles: "Searching for On-site Nuclear Balance against North Korea" in Comparative Strategy and "The Necessity to Discuss ‘Deterrence Failure’ Regarding North Korea’s Nuclear Threat" in International Studies.