It won’t be long. Security has so many holes.
Ralph Peter’s most recent war novel http://www.amazon.com/War-After-Armageddon-Ralph-Peters/dp/0765323559 has a scenario where armies and militaries revert back to basic tactics because each side has super-jammers that kill all comms and electronics on the other side
That’s what your post relates too. EMP strikes and jamming. And everyone is able to do it in the future according to Ralph Peters