Throughout the book, Perlroth provides a comprehensive analysis of globally significant events that illustrate the ways in which various governments and organizations have used digital espionage to interfere with issues of privacy and civil liberties. Zero-day exploits are commonly used in digital espionage campaigns, and Perlroth cites numerous examples of occasions when American and foreign government agencies used digital tools to spy on their own citizens and  on foreign civilians, corporations, and diplomatic targets. For billions of people, everyday life is inextricably entwined with digital activities and devices, and cyberespionage therefore has the potential to provide hostile actors with unprecedented access to sensitive personal data and real-time surveillance information.

Perlroth also conducts an incisive examination of the activities of the NSA, which often works in conjunction with the CIA and stands as the premier intelligence agency of the United States. The NSA’s TAO (Tailored Access Operations) team develops and deploys countless zero-day exploits in both domestic and international espionage activities. Within this context, the 2013 Snowden Leaks showed the agency’s willingness to spy indiscriminately on private citizens and allies, a major violation of the fundamental human right to privacy. The outraged determination with which Silicon Valley tech companies changed their practices to combat government infiltration echoes the public outcry sparked by these revelations.

In addition to critiquing the faults and failures of the United States with regard to digital espionage, Perlroth also bemoans the case of Ahmed Mansoor, whose criticism of Emeriti royalty resulted in years of life-ruining government surveillance and persecution, even prior to his arrest. She then seasons her arguments with a powerful example from her own experience; when she personally broke the story of the Mexican president’s illegal hacking of critics and opponents, she consequently became a target of digital espionage herself. Thus, by combining broader analyses of key events with concrete evidence of her own expertise, Perlroth builds a strong case in support of her desire to reform modern approaches to cybersecurity.

To further illustrate the global impact of digital espionage, Perlroth also examines China’s corporate espionage practices in America, which were honed on Chinese citizens first, with the goal of suppressing “undesirable” minorities known as the Five Poisons. As Perlroth notes, the targeting of individual dissidents and demographics erodes the civil liberties of all citizens because it discourages dissent and opposition to the ruling powers. It also makes targets vulnerable to persecution, blackmail, and acts of violence. Privacy is a fundamental human right that protects the most vulnerable in society from the whims of the powerful, and Perlroth uses a variety of concrete examples to illustrate this point, as when she outlines the unequal need for secrecy in conservative Alabama (239).

However, Perlroth also shows that digital espionage can be used to defend civil liberties. For example, hacktivist Sinan Eren used hacking to gain intel on the movements of Turkish law enforcement in order to help his fellow Kurds escape persecution and detention. Espionage tools can also be used to access classified information, such as harmful government policies and activities, and leaking this information to the public can prompt reform. However, such leaks can also have an indirectly detrimental effect on civil liberties, as when the Shadow Brokers unleashed tools for oppression into the world. Ultimately, Perlroth aptly describes the tool of digital espionage as a double-edged sword that can either promote certain benefits or wreak widespread harm.