The United States’ increased use of unmanned aerial vehicles to target individuals has already generated considerable moral and legal unease. Imagine, however, the dilemmas that will arise once machines not only are able to kill at a distance but also can decide whom to kill, without any opportunity for human deliberation or, possibly, hesitation. In this thoughtful meditation on technology and ethics, Riza, a fighter pilot and colonel in the U.S. Air Force, worries that robotics make it easier to go to war. But the concern that mechanical slaughter is replacing the work of discerning warriors is hardly new, and Riza exaggerates the role that robotics will play in future combat. Nonetheless, he performs a valuable service by raising the challenging issues of impunity and accountability.