There is a growing risk that the United States and its allies may face scenarios in which one or more adversaries could resort to the use of nuclear weapons in a regional conflict. In response to these growing risks, U.S. decision makers are reexamining the concept of wartime deterrence, which is about influencing enemy actions during an ongoing conflict. The risks of deterrence failure have been a focal point in the testimony of recent U.S. Strategic Command (STRATCOM) commanders, including General Anthony Cotton, who said during testimony in February 2024: “We must be ready when deterrence failed”.

To aid in this thinking and develop actionable insights for the U.S. policy and strategy communities, the Project on Nuclear Issues (PONI) invited a group of experts to develop competing strategies to respond to the failure of strategic deterrence. The current contributors to the project were each asked to respond to a scenario in which Russia and China would use near-simultaneous nuclear use on the battlefield. The strategies focused on four specific themes: strategic objectives, assurance to allies, military responses, and non-kinetic responses. The strategies demonstrate agreement on key issues, such as the importance of deterring conventional aggression and the relevance of non-kinetic responses to hostile nuclear use. But the strategies also highlight important areas of disagreement about the relative importance and feasibility of securing allies, at least relative to other strategic objectives; the desirability of a nuclear versus conventional response to deterrence failure; and what “winning” would look like in a scenario where strategic deterrence fails.

This publication was made possible by generous support from the Defense Threat Reduction Agency.