Well I think they could say that and the unit would then respond with x possible targets and the human operator would need to give the ultimate go-ahead. Point being that it would be bad if you have a bot with a machine gun and you tell it to kill everyone hostile with a gun in this area and it blasts that 13 yo kid with a fucking stick. They could identify targets, but a human would have to be the one okaying them.
If you lose communications then you’re shit out of luck. Though I guess you would have some backup system like if comms fail go back to base or hunker down etc and wait.