Sorry for taking this on such a weird tangent, but I've been reading the Culture stories and my immediate thinking was - why not? Missiles fly for a relatively long time compared to human decision making, let alone compared to optimized AI agents. There's notechnical barrier to having the missile be controlled by a conversational AI to which the intended recipient could appeal, negotiating with it to change its course.
I'm obviously not arguing that this is a good idea, but I wouldn't be that surprised if this is the future trajectory (sorry for the pun) of "smart weapons".