Drones have no real use on the battlefield, and they are too easily changed. It would take one great crack, and hundreds of drones could be turned against the manufacturers.
Putting your army in the hands of computers is folly. It is far easier to reprogram or convert a drone than a pilot.
It is a total dead-end in technology. The only good drones are cruise missiles, because they self-destruct by design.
I just want to say it loud and say it proud, the pentagon is full of blithering idiots. They are designing weapons and armies around international law loopholes and misguided ideas about American tolerance for casualties. 1) it's a loophole, so it is hardly legal anyways, and 2) there are no laws in war. 3) war weariness from lost soldiers/pilots is only a way for people who despise wars to appeal to their less empathetic countrymen. 4) In a real war, the lives saved by using drone pilots would be insignificant and irrelevant. 5) fighters are way harder to shoot down than drones, and only a handful of drones have been shot down, because the theaters they are operating in are not actual warzones.
The pentagon is also developing super tanks that will have no crew. Their stupidity knows no bounds. How could you even dream of deploying armaments that the only thing stopping the weapon from being turned against you is an encrypted signal program. ALL programs have backdoors. They have to for maintenance. Find that backdoor, and wait for the right moment to exploit it. To rely on a drone army is to rely on your cyber-guys being better than their cyber-guys. America only has 1/25th of the world's population. Many of America's "enemies" have more intelligent people than the entire population of America. And stealing a drone, much like using one, is a risk free operation. So in that regard, it is tit-for-tat. Mouse and trap.