The worry with drones is that there's no risk, apart from a bit of cash (insignificant from a military budget point of view); which might lead to less thought given to the reason for going out and killing people. When killing people is as easy as firing up the Xbox and there's no personal risk whatsoever (apart from the relatively minor one of a chewing out if you trash one) then the whole process becomes easier and that is quite possibly a dangerous thing. It becomes too easy to disassociate and forget that there's actual people with actual lives (briefly) in the crosshairs.
I'm worried that it will change the default thinking from "Do we REALLY need to do this" to "Fuck it, why not?"