Unmanned Aerial Vehicles (UAVs) make significant contributions to the war fighting capability of operational forces. The assumption is that piloted, remotely piloted, and autonomous vehicles have advantages and disadvantages in military operations, and that these vary in strategic significance for different levels of conflict. Since it is essential for the U.S. defense establishment to consider the strategic and technological implications of these types of aerial vehicles, this study is devoted to addressing the issues raised by the new generation of aerial vehicles. As technological advances increase the lethality of weapons on the modern battlefield, it is inevitable that UAVs will reduce the risks to humans in combat. If there is a fundamental constraint on the development of UAVs, it is that technology promises to find purely unmanned solutions to combat but cannot deliver on that promise. Political and military authorities should approach with caution the prospect of a world in which automated systems select military targets and employ lethal ordnance.