I'm pretty skeptical the U.S. military is concerned about wasted ammunition. They waste so much on training and preparation that anything wasted in combat is minimal.
> I'm pretty sure the first side to allow fully autonomous weapons will do so before the technology is ready
It doesn't have to be autonomous to be deployed before it's ready. Iran managed to should down a civil aircraft based on human error. The U.S. has done the same decades earlier. Clearly there were either technology or human process problems, I suspect that autonomous military robots will follow this trend.