The U.S. Department of Defense wants to enlarge the U.S. military's reliance on autonomous (i.e. self-directed) weapons in conflict. But a mission is not a person, it is a thing, and things cannot be held morally responsible. It is like saying that you want to hold your car responsible for breaking down on the way to work. You wouldn't say that your car "wronged" you, and you wouldn't seek to punish your car. Such a position on the ethics of autonomous systems reduces any questions of morality or responsibility.