In the development of American cybersecurity policy, deterrence has simultaneously grown more important and more controversial, leaving policymakers who confront mounting cyber threats tempted by deterrent strategies shrouded in doubts about their effectiveness. In Strategic Cyber Deterrence, Scott Jasper breaks down the theory and practice of deterrence within the realm of cyberspace and argues that the traditional approaches of deterrence by retaliation, denial, and entanglement fail as strategic options. Instead, Jasper advocates for achieving strategic deterrence by combining robust, resilient cyber defenses with capabilities to engage in aggressive but calibrated countermeasures. His engaging contribution carefully cuts through the prevailing “something must be done” approaches to deterrence in cybersecurity and offers a strategy tailored to the challenges and capabilities that define the cyber realm.