There was a Star Trek episode about this...

Robotics experts from around the world have called for a ban on autonomous weapons, warning that an artificial intelligence revolution in warfare could spell disaster for humanity.The open letter, published by the Future of Life Institute, has been signed by hundreds of AI and robotics researchers, as well as high-profile persons in the science and tech world including Stephen Hawking, Tesla CEO Elon Musk and Apple co-founder Steve Wozniak. Celebrated philosopher and cognitive scientist Daniel Dennett is among other endorsers who've added their names to the letter.Developments in machine intelligence and robotics are already impacting the tech landscape -- for instance, camera-equipped drones are prompting new debates on personal privacy and self-driving cars have the potential to revolutionise the automotive industry. However, many experts are concerned that progress in the field of AI could offer applications for warfare that take humans out of the loop.The open letter defines autonomous weapons as those that "select and engage targets without human intervention". It suggests that armed quadcopters that hunt and kill people are an example of the kind of AI that should be banned to prevent a "global AI arms race."