Edit: I was slowed down for posting too fast so I'm adding my reply to IntronExon here:
It's an interesting hypothetical but I'd argue its appeal is mostly in its simplicity with little evidence to support the claim. The instances you've cited happened either due to a failure of accurate intelligence or because intelligence indicated the structure was being used by enemy combatants. It's very possible to arrive at the conclusion that any unnecessary casualties which occurred happened as a result of poor military intelligence which better reconnaissance drones could help with. It's equally possible that someone working on this kind of technology could see its field use against groups like ISIS as evidence that weaponized drones are a useful tool in fighting terrorist organizations. Obviously neither of these will be true in every instance, but without strong evidence it's hard to believe that the matter is as simple as "some people are just unemphatic".