The world has entered an era of drone wars. In four major interstate wars in the last five years—those in Libya, Nagorno-Karabakh, Syria, and Ukraine—armed drones played a dominant, perhaps decisive, role. And yet the debates about drones still center on their use against nonstate actors, such as the Taliban, or speculation about their potential role in wars between the United States and near competitors, such as China. Those discussions have led many scholars to conclude that drones are so complicated and vulnerable as to be of limited use or relevance to wars between states. Some observers argue that drones may even promote international stability: countries may be less likely to escalate a conflict if a drone, rather than an aircraft with a human pilot, is shot down.