narrow-minded
This seems to me to be a very narrow-minded solution to the terrorist threat. A 'solution' that I think will lead to more loss of life rather than less.
My view is that terrorists simply want to make a point. The means to their ends has variously involved hijacking airliners and diverting them, right up to flying them into buildings and/or blowing them up.
I think that given autonomous ground control from authorities, in lieu of terrorists being able to hijack and divert, the terrorists will be more inclined towards blowing them up outright; especially considering communication difficulties between themselves and the ground controllers should the authorities be willing to grant/control a safe diversion as appeasement.
This will unnessicarily endanger passengers and crew of hijacked airplanes especially considering there seem to be plenty of safeguards against 'unaccountered for' airplanes approaching metros (read countless reports of airplanes being escorted away from cities by jet fighters).