Risk Analysis Methods
for Nuclear War and
Nuclear Terrorism

_____

Committee on Risk Analysis Methods for Nuclear War
and Nuclear Terrorism

Board on Mathematical Sciences and Analytics
Division on Engineering and Physical Sciences

Nuclear and Radiation Studies Board
Division on Earth and Life Studies

Committee on International Security and Arms Control
Policy and Global Affairs

Consensus Study Report

NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001

This activity was supported by the Department of Defense. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

International Standard Book Number-13: 978-0-309-68998-4
International Standard Book Number-10: 0-309-68998-8
Digital Object Identifier: https://doi.org/10.17226/26609

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2023. Risk Analysis Methods for Nuclear War and Nuclear Terrorism. Washington, DC: The National Academies Press. https://doi.org/10.17226/26609.

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COMMITTEE ON RISK ANALYSIS METHODS FOR NUCLEAR WAR AND NUCLEAR TERRORISM

WILLIAM C. OSTENDORFF, U.S. Navy (Retired), Co-Chair

M. ELISABETH PATÉ-CORNELL (NAE), Stanford University, Co-Chair

DAVID L. BANKS, Duke University

VICKI M. BIER, University of Wisconsin–Madison (Retired)

MATTHEW G. BUNN,¹ Harvard University

NANCY J. COOKE, Arizona State University

RAYMOND JEANLOZ (NAS), University of California, Berkeley

MADHAV V. MARATHE, University of Virginia

RICHARD W. MIES, The Mies Group, Ltd.

GREGORY S. PARNELL, University of Arkansas

SCOTT D. SAGAN, Stanford University

JAMES SCOURAS, Johns Hopkins University Applied Physics Laboratory

PAUL SLOVIC (NAS), Decision Research and University of Oregon

ALYSON G. WILSON, North Carolina State University

Staff

CARL-GUSTAV ANDERSON, Program Officer, Board on Mathematical Sciences and Analytics, Co–Study Director (until February 2022)

JENNY HEIMBERG, Senior Program Officer, Nuclear and Radiation Studies Board, Co–Study Director

MARGUERITE SCHNEIDER, Administrative Coordinator, Intelligence Community Studies Board

MICHELLE SCHWALBE, Director, Board on Mathematical Sciences and Analytics

CHARLES FERGUSON, Senior Board Director, Nuclear and Radiation Studies Board

BRITTANY SEGUNDO, Program Officer, Board on Mathematical Sciences and Analytics

MICAH LOWENTHAL, Director, Committee on International Security and Arms Control

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¹ Resigned February 2022.

BOARD ON MATHEMATICAL SCIENCES AND ANALYTICS

MARK L. GREEN, University of California, Los Angeles, Chair

HÉLÈNE BARCELO, Mathematical Sciences Research Institute

BONNIE BERGER (NAS), Massachusetts Institute of Technology

RUSSEL E. CAFLISCH (NAS), New York University

DAVID S. CHU, Institute for Defense Analyses

DUANE COOPER, Morehouse College

JAMES H. CURRY, University of Colorado Boulder

RONALD D. FRICKER, JR., Virginia Polytechnic Institute and State University

TRACHETTE JACKSON, University of Michigan

LYDIA E. KAVRAKI (NAM), Rice University

TAMARA G. KOLDA (NAE), Sandia National Laboratories

PETROS KOUMOUTSAKOS (NAE), Harvard University

RACHEL KUSKE, Georgia Institute of Technology

YANN A. LECUN (NAS/NAE), Facebook

JILL PIPHER, Brown University

YORAM SINGER, WorldQuant

TATIANA TORO, University of Washington

LANCE A. WALLER, Emory University

AMIE WILKINSON, University of Chicago

KAREN E. WILLCOX (NAE), The University of Texas at Austin

Staff

MICHELLE K. SCHWALBE, Director

HEATHER LOZOWSKI, Senior Finance Business Partner

BRITTANY SEGUNDO, Program Officer

NUCLEAR AND RADIATION STUDIES BOARD

WILLIAM H. TOBEY, Los Alamos National Laboratory, Chair

JAMES A. BRINK, Massachusetts General Hospital, Vice Chair

SALLY A. AMUNDSON, Columbia University

STEVEN M. BECKER, Old Dominion University

AMY BERRINGTON DE GONZALEZ, National Cancer Institute

MADELYN R. CREEDON, Green Marble Group, LLC

SHAHEEN A. DEWJI, Georgia Institute of Technology

PAUL T. DICKMAN, Argonne National Laboratory

STEPAN KALMYKOV, Moscow State University

ALLISON M. MACFARLANE, University of British Columbia

ELEANOR MELAMED, National Nuclear Security Administration (Retired)

PER F. PETERSON (NAE), University of California, Berkeley

R. JULIAN PRESTON, Environmental Protection Agency

MONICA C. REGALBUTO, Idaho National Laboratory

HENRY D. ROYAL, Washington University in St. Louis

Staff

CHARLES FERGUSON, Director

LESLIE BEAUCHAMP, Program Assistant

DARLENE GROS, Senior Program Assistant

JENNY HEIMBERG, Senior Program Officer

MICHAEL JANICKE, Senior Program Officer

OURANIA KOSTI, Senior Program Officer

LAURA LLANOS, Financial Business Partner

COMMITTEE ON INTERNATIONAL SECURITY AND ARMS CONTROL

RAYMOND JEANLOZ (NAS), University of California, Berkeley, Chair

LINTON F. BROOKS, Independent Consultant

MATTHEW G. BUNN, Harvard University

STEVEN A. FETTER, University of Maryland

DAVID R. FRANZ, Kansas State University

RICHARD L. GARWIN (NAS/NAE/NAM), IBM Thomas J. Watson Research Center

ROSE E. GOTTEMOELLER, Stanford University

DIANE E. GRIFFIN (NAS/NAE), Johns Hopkins University

MARGARET E. HAMBURG (NAM), Nuclear Threat Initiative

MORIBA K. JAH, The University of Texas at Austin

ALASTAIR I. JOHNSTON, Harvard University

LORA LANNAN SAALMAN, Stockholm International Peace Research Institute

ROBERT H. LATIFF, R. Latiff Associates

JAMES W. LEDUC, Galveston National Laboratory

HERBERT S. LIN, Stanford University

DOUGLAS L. LOVERRO, Loverro Consulting, LLC

RICHARD A. MESERVE (NAE), Covington & Burling, LLP

RICHARD W. MIES, The Mies Group, Ltd.

PETER PALESE (NAS/NAM), The Mount Sinai Hospital

VICTORIA A. SAMSON, Secure World Foundation

JIM TIMBIE, Stanford University

JOHN G. HILDEBRAND (NAS), University of Arizona, Ex Officio Member

Staff

MICAH LOWENTHAL, Director

NICOLE CERVENKA, Research Associate

RITA GUENTHER, Senior Program Officer

HOPE HARE, Administrative Assistant

MARIE KIRKEGAARD, Program Officer

BENJAMIN RUSEK, Senior Program Officer

Reviewers

This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each consensus study as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the charge. The review comments and draft manuscript remain confidential to protect the integrity of the process.

We thank the following individuals for their review of this report:

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the content of the report nor did they see the final draft before its release. The review of this report was overseen by CHRIS G. WHIPPLE (NAE), ENVIRON (retired), and GEORGE APOSTOLAKIS (NAE), Massachusetts Institute of Technology. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.

Contents

PREFACE

SUMMARY

1 INTRODUCTION

Committee Task and Scope of Work

Audience for This Report

Committee Interpretation of the Statement of Task

2 THE THREAT OF NUCLEAR WAR AND NUCLEAR TERRORISM: CLASSES OF SCENARIOS

Device Types and Scales of Events

Classes of Nuclear War Scenarios

Classes of Nuclear Terrorism Scenarios

3 THE HISTORY AND LITERATURE OF RISK ASSESSMENT FOR NUCLEAR WAR AND NUCLEAR TERRORISM

The History and Literature of Risk Assessment for Nuclear War

Insights Relevant to the Risks of Nuclear War

The History and Literature of Risk Assessment for Nuclear Terrorism

Insights Relevant to the Risks of Nuclear Terrorism

Conclusion

4 THE USE OF RISK ASSESSMENT FOR NUCLEAR WAR AND NUCLEAR TERRORISM

Threats of Nuclear War

Threats of Nuclear Terrorism

Consequences of Nuclear and Radiological Weapons Use

The Challenges of Assessing the Overall Risks of Nuclear War and Nuclear Terrorism

Conclusions

5 THE STRUCTURE OF RISK ANALYSIS

Risk Definitions

Risk Analysis as a Systematic Process

Available Sources of Evidence

Assumptions in Risk Analysis

U.S. Strategic Assumptions About Nuclear Risks

Conclusions

6 RISK ANALYSIS METHODS AND MODELS

Overview of Methods

First-Strike Stability Analysis

Probabilistic Risk Assessment

Order-of-Magnitude Estimates

Nuclear Effects Simulations

Game Theoretical Approaches

Modeling of Adversaries

Other Models

Conclusion

7 RISK INFORMATION AND RISK MANAGEMENT DECISIONS

Empirical Study of Judgment and Decision Making

Thinking About Risks

Communicating Risk Analysis Results

Conclusion

8 CONCLUSIONS AND NEXT STEPS

REFERENCES

APPENDIXES

A U.S. Strategic Assumptions About Nuclear Risks

B Types of Uncertainty

C U.S. Policy-Making Structure for Nuclear War and Nuclear Terrorism

D Agendas of Committee Meetings

E Committee Member Biographies

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Preface

This report was mandated by the National Defense Authorization Act for Fiscal Year 2020, which directed the Department of Defense to contract with the National Academies of Sciences, Engineering, and Medicine (the National Academies) to explore the nature and the use of risk analysis methods in assessing nuclear war and nuclear terrorism risks.

The congressional mandate required the National Academies to appoint a committee to address the task in two phases. Phase I of the study is to develop an unclassified report based on access to unclassified information, focusing primarily on a study of risk analysis methods that might be used in assessing the risks of nuclear war and nuclear terrorism. Phase II will expand the focus to include an analysis of the role that the methods and assumptions in risk analysis may play in U.S. security strategy, and it is expected to produce a classified report along with an unclassified summary. The current report is the result of Phase I.

Some readers may ask why this Phase I report does not cover an in-depth analysis of the risks of nuclear war given the Russian Federation invasion of Ukraine. The statement of task for this report is clear in its call for a study of risk analysis methods that might be used in assessing the risks of nuclear war or nuclear terrorism. It is not the charter of this committee to actually conduct its own risk analysis, whether of the risks of nuclear weapons employment in the conflict in Ukraine or in other scenarios associated with nuclear war or nuclear terrorism. The actual risk analysis is in the domain of risk analysis professionals and policy makers in the

Executive Branch. It is possible, however, that the Phase II classified portion of the committee’s work may explore further some aspects of different methods of analysis of the nuclear risks associated with the current Ukrainian conflict.

We thank all committee members for their significant contributions to this challenging study. We are most grateful for their candor and collegiality. We would further like to thank the National Academies staff co-directors Carl-Gustav Anderson and Jenny Heimberg. We also thank Michelle Schwalbe for her assistance in the report review process.

Bill Ostendorff and Elisabeth Paté-Cornell, Co-Chairs
Committee on Risk Analysis Methods for Nuclear War and Nuclear Terrorism