> civilians are already getting blown up all the time by systems that do not even attempt to make any distinction between civilians and soldiers: artillery shells, mortars, landmines, rockets, etc.

Right, and everytime that happens because of miscalculations by our government they lose the very real and important public license to continue. Ultimately modern wars led by democracies are won by public desire to continue them. The American public can become very hesitant to wage war very fast, if we unleash Minority Report on the world for revenge