Recent advances in AI mean that it would now be possible to develop autonomous weapons – systems which are capable of making automated decisions to take human life. Elon Musk, DeepMind and others have signed a pledge never to create AI weapons:
"We the undersigned agree that the decision to take a human life should never be delegated to a machine. It goes on to warn "lethal autonomous weapons, selecting and engaging targets without human intervention, would be dangerously destabilizing for every country and individual."
https://www.forbes.com/sites/samshead/2018/07/18/elon-musk-deepmind-founders-and-others-promise-not-to-make-lethal-ai-weapons/#165c8a1b7269
The signatories have promised to “neither participate in nor support the development, manufacture, trade, or use of lethal autonomous weapons.”