One Question for the time traveler….

You mention a full scale nuclear weapons deployment as a result of WWIII. You also mention that electronics, computers, and even the Internet still functioning some time after that. Can you explain how these devices (and more importantly the facilities that made them) withstood the EMP airbursts associated with any full scale nuclear war? Every electronic device would be inorperable after such an event and it would take decades (if even possible) to rebuild the infrastructure to allow for the building of an electric razor, let alone an Internet.