Living With a Nuclear-Arming North Korea: Deterrence Decisions in a Deteriorating Threat Environment

Executive Summary

As the latest chapter in US diplomacy aimed at denuclearizing North Korea comes to another unhappy end, it is time to take stock. As the diplomatic strategy adjusts to new realities, it is also time to revisit deterrence strategy. Having been put on the back burner these last few years, that strategy is in need of attention. Some difficult choices lie ahead about how to further adapt and strengthen that strategy and the associated regional deterrence architecture. The most contentious issues are likely to be choices about nuclear policy and posture. This report reaches the following key judgments and recommendations:

• North Korea’s progression from the nuclear threshold to a heavily armed nuclear state with intercontinental reach is doing serious damage to the foundations of strategic stability in Northeast Asia by eroding confidence in the ability and will of the United States to fulfill its security guarantees to South Korea and Japan.
• While working for denuclearization, the United States, South Korea, and Japan have also been working to adapt and strengthen deterrence so as to stay ahead of the emerging threat. This project was put on the back burner in recent years as a sign of good faith. It is time to bring it back to the front burner.
• The US nuclear umbrella, a legacy of decisions made in very different security environments in 1991 and 2010, is no longer fit for purpose as presently composed. It must be modified to enable improved signaling of collective resolve to stand up to North Korea’s nuclear bullying.
• A more “NATO-like” approach could serve the US-ROK and US-Japan alliances well. But this requires coming to terms with confusion about how NATO practices extended nuclear deterrence. A more NATO-like approach would entail changes not just to the posture of US nuclear forces but also to the organization and practice of consultations as well as new approaches to strategy and policy development.