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You techie diehards out there may want to consider a second option........Change FCC, UL, EU, and CISPR standards to phase in all devices be manufactured to withstand EMP, including your VCR, coffee pot, and automobile so that economy of scale makes EMP affordable and implemented over the lifetime of a few cycles of consumer goods.

Unfortunately this is not really a feasible option. More and more electronic devices are being implemented as a single chip design. It is much more expensive to design a chip that can withstand any serious amount of EM radiation without malfuncioning that one that cannot. It took an amazing amount of money, work, and time to develop the radiation hardened Pentium, and that was simply modifying a working design. Basically radiation hardening really restricts what you can do in VLSI, and it is hard enough to squeeze that many transistors into that small of a space without any additional constraints.

There is a reason that radhard processors or so far behind conventional ones, and it isn't a lack of money or interest.

If you are talking about shielding for the devices themselves that means instead of slapping a simply plastic box on the device you would have to spend a lot more money on first designing the enclosure, on the raw materials (metal rather than plastic), and finally on the manufacturing. Plastic injection molding is a lot cheaper than metal fabrication.

Besides, more and more devices are becoming wireless. How exactly are going going to protect a laptop when it has two 12" antennas in its screen, or your cell phone, the receiver on top of your TV with the 12' FM dipole dangling off the back, etc. For that matter I expect that the 6' cord connecting your headphones to your ipod is a liability.

Not saying that certain devices can't be made impervious, but those should be the ones really necessary to preserve human life. You were right in saying that the extra expense isn't really worth it for consumer electronics.

-paridel

Conductive coatings sprayed on the insides of plastic housings, integrated to frame ground is cheap. You don't need metal enclosures. It's easy to apply, but a bit toxic to spray. Properly sprayed, a plastic monitor housing and a carbon coated sterling plated stainless screen mesh in the viewing area does nicely. Shielding a processor is also very easy. Unfortunately, the software programs which auto design circuit boards as well as circuit board engineers use abhorent thinking when it comes to what they do. It makes no sense from a shielding perspective. Almost certainly catastrophic by design. I once had a main processor about three inches from a DC to AC transformer driving a fluorescent operator display with about 2,500 Volts AC. It generated so much of an E-field and H-field that it caused the processor to crash several times per hour. The engineers couldn't understand why? I had to remove the transormer from the main board and box it inside a can, connecting it with shielded wire and then make it all fit back inside the same space. The funny thing is that the energy created then flowed theu the wiring into the display laminate glass and popped out there. I used mesh there and connected it to frame ground, where it got sent to never-never land.