TFA explicitly points out that the civilians will not be pulling the trigger. They will be used only for Combat Air Patrols (a term that seems just a bit inappropriate) that are for data gathering and surveillance only. The trigger pullers will be active duty military.
The problem, in TFA's eyes is that this represents a slippery slope - how many degrees of separation do you need in a military setting?
IIRC, the air force has about four major protocol points that they follow in order to ensure that drone strikes are legal. One of those is that the person pulling the trigger be military so that you are ensured a direct chain of command, i.e. legal authority to kill others on behalf of the state, (this also ensures they get qualified immunity from lawsuits.)