"The Department of Defense's shift in 2018 to a posture of persistence in operations and forward cyber defense is an important step toward achieving better national cybersecurity. The United States' Defend Forward Cyber Strategy is an indispensable contribution to understanding this novel strategic approach and the important, related questions raised at the intersection of domestic and international law and policy. The essays in this volume, written by leading experts from the academy and the U.S. government, tackle these questions with unique expertise and exceptional insight. They provide invaluable guidance for ensuring the U.S. can defend forward in cyberspace consistent with its commitment to the rule of law.

" -- Admiral (retired) Michael S. Rogers, Former Director, National Security Agency and Commander, U.S. Cyber Command "America's Defend Forward cyber strategy is a momentous change in the approach to cyber conflict that has, to date, been under analyzed. This new groundbreaking volume begins that inquiry. It is the first thorough and thoughtful account of the legal underpinnings of Defend Forward. The analysis is of such high quality that it will, no doubt, be the baseline examination that defines the field for years to come." -- Paul Rosenzweig, Former Deputy Assistant Secretary for Policy, Department of Homeland Security "Goldsmith's volume offers a welcome tour d'horizon of the domestic, international, and comparative legal issues associated with the United States' Defend Forward strategy and the tactics of persistent engagement that support it.

With chapters by leading government and academic experts, this book surveys key legal restraints and authorities under the U.S. Constitution and other domestic laws as well as all the relevant international legal topics such as sovereignty, intervention, counter-measures, and attribution. Supplemented by comparisons to Israeli and U.K. approaches, the result is not simply an introduction to an under-explored topic, but a lasting--and significant--contribution to the field." -- Duncan B. Hollis, Laura H.

Carnell Professor of Law, Temple Law School.