In reply to The Lemming:
Well it seems we can make radio controlled tanks with no need for a driver. The issue it of course signal jamming, or worse still, interception so sending new signals to make them turn around and fire on tier own side.
I guess it could be solved by having full autonomous tanks / or drones which aren't remotely controlled but pre-programmed to go out into an environment, reach and destroy a target and work out for its self how to get there and what to kill / destroy in order to protect its self while it carries out its mission.
There would be ethical considerations to make but I think sooner or later we'll build them. We're getting there with self driving cars, on road or off road so that element already exists, the extra bit is sticking a gun to it and having some sort of friend/foe identification system by which it decides to fire or not.