if country A declares war on country B, and country A marches robots out for the offense, and country B deploys robots for defense, why is that not a war?
and why can't they settle for peace before people start getting killed?
of course, considering human stubbornness, one side probably won't be saying "mercy" until actual people are being killed
but it is possible to begin and end the war with only robotic combatants
i mean you could also say
"Will never happen. At that point, you may as well settle your differences with a football match. If you're not killing people with swords, and only pointing guns at each other from a distance, it isn't a war. you have to be in the other guy's face and feel his warm blood and his life force ebb in his final breath, for it to be real war"
"Will never happen. At that point, you may as well settle your differences with a football match. If you're not killing people on the field of battle with archers, and only lobbing plague victims over city walls, it isn't a war. you have to meet each other on a proper field of battle, and not target civilians in low cowardly ways, for it to be a real war"
you are arguing form a narrow understanding of what "war" means. if history teaches us anything, mankind's parameters for violent warfare are continuously evolving and radically far reaching