Japan’s Nuclear Hedge: Beyond “Allergy” and Breakout

{
  "authors": [
    "James L. Schoff",
    "Richard J. Samuels"
  ],
  "type": "other",
  "centerAffiliationAll": "dc",
  "centers": [
    "Carnegie Endowment for International Peace"
  ],
  "collections": [],
  "englishNewsletterAll": "asia",
  "nonEnglishNewsletterAll": "",
  "primaryCenter": "Carnegie Endowment for International Peace",
  "programAffiliation": "AP",
  "programs": [
    "Asia"
  ],
  "projects": [],
  "regions": [
    "East Asia",
    "Japan"
  ],
  "topics": [
    "Nuclear Policy"
  ]
}

Other

Japan’s Nuclear Hedge: Beyond “Allergy” and Breakout

With the U.S. nuclear umbrella shrinking and nuclear threats in Asia becoming greater and more complex, analysts cannot dismiss a nuclear-armed Japan as a purely academic exercise.

By James L. Schoff and Richard J. Samuels

Published on Oct 2, 2013

Source: National Bureau of Asian Research

This chapter examines the future of Japan’s hedged dependence on U.S. extended deterrence and encourages more imaginative thinking about potential outcomes and strategic implications as the second nuclear age unfolds.

Main Argument

With the U.S. nuclear umbrella shrinking and nuclear threats in Asia becoming greater and more complex, analysts cannot dismiss a nuclear-armed Japan as a purely academic exercise.
While we do not expect a Japanese nuclear breakout in the near term, Washington’s traditional reassurances—massive numbers of weapons deployed in theater and a robust regional presence—have given way to a less convincing reliance on specific weapon systems amid a diminishing conventional military advantage.
Enhanced bilateral dialogue has been used to strengthen the alliance, but Japan’s neighborhood is more dangerous than ever, and the many domestic constraints on Japanese nuclear breakout—cultural, political, and institutional—could become less restrictive than before.

Policy Implications

A U.S. decision to sustain extended deterrence will require significantly more resources and attention than heretofore assigned.
A more integrated, alliance-based approach to deterrence might therefore become attractive.
Alternatives to Japan’s long-practiced nuclear hedge may come to have appeal in Tokyo or Washington.
Coordinated regional action to limit North Korea’s nuclear development remains critical.

Read the full chapter here.

This chapter is from Strategic Asia 2013-14: Asia in the Second Nuclear Age. Read more about Strategic Asia, including information on how to order the complete book, here.

About the Authors

James L. Schoff

Former Senior Fellow, Asia Program

James L. Schoff was a senior fellow in the Carnegie Asia Program. His research focuses on U.S.-Japan relations and regional engagement, Japanese technology innovation, and regional trade and security dynamics.

Richard J. Samuels

Nuclear Policy East Asia Japan

Carnegie does not take institutional positions on public policy issues; the views represented herein are those of the author(s) and do not necessarily reflect the views of Carnegie, its staff, or its trustees.

More Work from Carnegie Endowment for International Peace

Paper
China’s Police and Security Cooperation Agreements
China’s Ministry of Public Security is often portrayed as a domestic law enforcement agency, but it is also a global security actor. This paper explores how MPS has used international law enforcement and security cooperation agreements—over 200 since 2006—to advance China’s vision of security in a changing global environment.
Sophie Zhuang, Sheena Chestnut Greitens, Cameron Waltz
Commentary
Strategic Europe
Europe Should Not Let Nuclear Nonproliferation Die
Amid uncertainty caused by the Iran war, the global drive for nonproliferation has stalled. With Europe diplomatically marginalized and countries reassessing their nuclear options, efforts to curb the spread of nuclear weapons risk becoming irrelevant.
Jane Darby Menton
Commentary
Post U.S.-China Summit: Managed Instability
The U.S.-China Summit produced a welcome commitment to build a constructive, strategically stable relationship. However, the United States has a full agenda, including the USMCA review beginning this week, that will likely target Chinese practices of concern. If China views these efforts as inconsistent with the agreements reached in Beijing, it may slow or halt progress in response.
Barbara Weisel
Commentary
Carnegie Politika
Are Russia-Japan Relations Really Warming Up?
The truth is that Japan’s government is seeking a degree of reengagement but at a vastly reduced level than under Abe. Most significantly, Japan has shown no willingness to ease sanctions.
James D.J. Brown
Commentary
Diwan
Corrupted by Absolute Power
In an interview, Marc Lynch discusses his new book decrying the post-1990 U.S.-dominated order in the Middle East.
Michael Young

More Work from Carnegie Endowment for International Peace

Recruit polices vow as they join in the police at Beijing Public Security Bureau on February 18, 2011 in Beijing, China. (

Paper

China’s Police and Security Cooperation Agreements

China’s Ministry of Public Security is often portrayed as a domestic law enforcement agency, but it is also a global security actor. This paper explores how MPS has used international law enforcement and security cooperation agreements—over 200 since 2006—to advance China’s vision of security in a changing global environment.

Sophie Zhuang, Sheena Chestnut Greitens, Cameron Waltz

Commentary

Strategic Europe

Europe Should Not Let Nuclear Nonproliferation Die

Amid uncertainty caused by the Iran war, the global drive for nonproliferation has stalled. With Europe diplomatically marginalized and countries reassessing their nuclear options, efforts to curb the spread of nuclear weapons risk becoming irrelevant.

Jane Darby Menton

Chinese President Xi Jinping interacts with U.S. President Donald Trump during a state banquet at the Great Hall of the People on May 14, 2026 in Beijing, China.

Commentary

Post U.S.-China Summit: Managed Instability

The U.S.-China Summit produced a welcome commitment to build a constructive, strategically stable relationship. However, the United States has a full agenda, including the USMCA review beginning this week, that will likely target Chinese practices of concern. If China views these efforts as inconsistent with the agreements reached in Beijing, it may slow or halt progress in response.

Barbara Weisel

Commentary

Carnegie Politika

Are Russia-Japan Relations Really Warming Up?

The truth is that Japan’s government is seeking a degree of reengagement but at a vastly reduced level than under Abe. Most significantly, Japan has shown no willingness to ease sanctions.

James D.J. Brown

Commentary

Diwan

Corrupted by Absolute Power

In an interview, Marc Lynch discusses his new book decrying the post-1990 U.S.-dominated order in the Middle East.

Michael Young