Alfred Nobel’s invention of dynamite was a boon to major infrastructure projects around the world, but the explosive was also adopted by anarchists determined to blow up heads of state. A young sergeant named Mikhail Kalashnikov figured out how to improve the standard assault rifle used by the Soviet army in World War II. The gun that still bears his name is easy to use, reliable, and durable—and became the weapon of choice for terrorists and militias around the world. In this meticulously researched book, Cronin shows how groups such as the Islamic State (or ISIS) exploit new technologies such as the Internet, smartphones, autonomous vehicles, and artificial intelligence. Cronin hardly wants innovation to stop just because of potentially malign applications. Instead, she argues that governments must develop countermeasures to preempt militants from co-opting innovations to catastrophic effect.