I can think of two incidents where this technology may have helped save lives.... The shooting down of Civilian Aircraft by the American Warship and further back in time, the shooting down of the civilian aircraft by the Russian Mil. But isn't this idea this just adding to the hype and playing into the terrorists hands? Surely a measure of risk management, and personal safety, says I am not going to fly into any War Zone or other high risk area.... We train our military for that and they have the proper skills, equipment and Intel to perform that task.
What will be the next steps? Training the CC to be waist and tail gunners during TO and Landing? (I can just imaging the local airport security... No, you can't take that bottle of water or the leatherman through but the 500 rounds of ammo is ok)
Would aircraft with this system fitted be targeted by highjackers as they should be more difficult to shoot down? Would this become a MEL item

(ie the financial impact if the aircraft was shot at and it was found the system was inop).
The world seems to be getting crazier to me each day... or I am just getting old