re flying over war zones. in my day flight ops would present captains with routes that were open, obviously, and any official info on activity (wars, Danger and Restricted Areas etc ) that he needed to know about. the captain would then decide either to accept the route or insist on changes. thats the individual decision taken care of on the day. meanwhile the airline management monitors the rolling situation and makes policy decisions on whether to fly or not to fly a route over a specific period.
Now we have the FAA (and others) in response to concerns over flights in war zones finally issuing firm instructions. is it not ironic if not bonkers that Israel decides this is politically unacceptable to them and almost certainly orders that poor old Kerry has to ignore the instructions, or else.....