Buchanan’s handy book offers a substantial and measured history of cyberattacks in recent decades. Buchanan traces the progression of hacking operations beginning with the early efforts of the U.S. National Security Agency and the United Kingdom’s Government Communications Headquarters, or GCHQ, agencies that intercept all sorts of communications—including those of supposedly friendly governments. Many countries now engage in hacking in the pursuit of their national interests. The joint U.S.-Israeli operation that transmitted the Stuxnet virus that sabotaged centrifuges in Iran was discovered in 2010. Russia easily shut down Ukraine’s energy supplies through hacking in 2016 and famously meddled in the U.S. presidential election that same year by hacking the email accounts of Democratic Party officials and the chair of Hillary Clinton’s campaign. China has used hacking for the purposes of industrial sabotage. The 2013 revelations of the former NSA contractor Edward Snowden showed how Western governments did their spying. Despite the growing ubiquity of cyberattacks, Buchanan also highlights their limits as a means of coercion or as a way of sending a message.