I saw one of those military tv shows saying that a EMP burst in the air, I forget the exact altitude, could essentially turn the lower 48 states into the Dark Ages over night. You can protect your stuff with faraday cages but they are pretty expensive. Just imagine the chaos that would ensue if the lights everywhere suddenly went off.
faraday cages are not really expensive just very cumbersome. A faraday cage is just a box made out of conductive material. This prevents the electrical pulse from impacting whatever is inside.
On a small scale a simple metal box will protect small electronic items. Of course its hard to use them while they are in the box.
A Faraday cage doesn’t have to be expensive... All you need is a wooden ammo crate, some aluminum foil, aluminum tape (used for sealing ductwork), and a ground wire. Place the items to be protected inside, cover the box with the foil, secure the foil with the aluminum tape, and then fasten the ground wire to the aluminum covering the box and then to a ground rod. It is important that you run the ground wire to a good ground, and do not use the ground circuit found in you home. Use a separate gound rod. Easy...