Terminators or protectors? Rise of the robot soldiers may be closer than you think Murderous: The robots of the Terminator films fit the more destructive popular image of mechanised warfare. Every discussion of robots and warfare will always come back to one, or both, of two science-fiction touchstones: Skynet and Asimov. Skynet, the artificial intelligence defence system described in the Terminator films, gains self-awareness and immediately attempts to wipe out humanity. In Isaac Asimov's robot stories, he imagines "three laws of robotics," the first of which instructed all robots: "A robot may not injure a human being or, through inaction, allow a human being to come to harm." Those are the options, popularly understood: robot murderers trying to destroy mankind; or pacifist automatons barred by their programming from hurting humans. An MQ-9 Reaper drone flying at Creech Air Force Base in Nevada, US. If a group of activists with the splendid name "The Campaign to Stop Killer Robots" is to be believed, we are now at a watershed: we can choose between, crudely speaking, a version of one of these two futures. Representatives of 117 nations have been addressing a United Nations committee to discuss the use of "fully autonomous weapons" - battle robots, to you and me. It isn't all that long ago that this would have been a matter for science fiction, but in recent years it has become an increasingly imminent concern. The use of drones, or "unmanned combat air vehicles," in warfare and assassinations has become widespread, if controversial. Two dozen countries are known or believed to use armed unmanned aircraft of varying degrees of sophistication. Britain and the US use heavily armed, high-flying drones such as the MQ-9 Reaper, which can stay in the air for 14 hours at a time while carrying more than half a tonne of laser-guided bombs and missiles. Since Barack Obama became President, one US senator estimates, more than 4000 people have been killed in US military drone strikes. These drones, however, have human pilots - often sitting thousands of kilometres away. "The main military advantage of automated weapons over existing drones is that they're quicker to respond, and therefore could be used in greater numbers, without humans having to control every single one," says Professor Michael Clarke, director-general of the Royal United Services Institute and a defence adviser to the British government. At the moment, all drones still require an active decision to fire. In future, Clarke says, it might be a bit more complicated. "The rules of engagement will most likely be that a target would be defined, and then a particular time frame and area would be identified where the system would make its own decisions," he says. The question of the ethics of robots is a complicated one: who is responsible if a robotic soldier destroys a school instead of a military base? Is it the manufacturer, the designer, the operator? The general in command? There may, however, be moral advantages to using robots in warfare. Robot soldiers, as The Economist pointed out last year in a discussion of the ethics of automated warfare, will not carry out revenge attacks on civilians, or rape people, or panic in the heat of battle and shoot their allies. The world is some way from entirely autonomous weapons, but Paul Cornish, a professor of strategic studies at the University of Exeter, suspects the military will be wary of using them, for operational rather than ethical reasons. I just don't think the military mind would like the idea of a lethal weapon going off on its own on the battlefield: they'll want it to be connected by a link of some sort, and if the link breaks they'll want it to disengage. We don't, certainly for the time being, need to worry about programming a simulacrum of morality into robot soldiers, he says, because military commanders would be unwilling to unleash those robot soldiers without human oversight anyway. That may change as the weapons become more sophisticated, but their actions will still be limited by military law. That is, at least, in the West, where these weapons are closest to being developed. "We have to assume the Chinese will have their own version at some point," Clarke says. "We don't know whether the Chinese will have the same stringent rules of engagement as Britain and America," he adds. They last fought in 1979, in Vietnam, and it was a different world, technologically. But if other forms of Chinese behaviour are any guide, they may have a different attitude to the rule of law to ours, to put it mildly. The Campaign to Stop Killer Robots, then, might have reasons to be worried. But in the West, automated weapons would be just as subject to the laws of war as all the tools we use already. Whether those laws are too stringent, or not stringent enough, is a another question. But, says Cornish: "In recent years, the legal oversight of military operations has become so intense that the notion that we could unleash a lethal force with no such oversight is nonsense."