Regarding EMP. Its interesting that in July it was 50 years since the American Starfish Prime test in the south pacific. Which although being 900 miles away the blast destroyed street lights and telephone systems in Hawaii. A single nuclear weapon detonated at altitude over the US or Europe would send us back to the stone age. For a rogue nation that can't hope to win a conventional nuclear exchange I think it would be a tempting idea. But people think you're a nutter if you mention it seriously.
I found an interesting web page with some limited information on the Soviet EMP tests in Kazakhstan and the damage done by what they called test 184. (there's some interesting little titbits) As well as some interesting ideas on EM shielding.
http://www.futurescience.com/emp.html
I've done significant research on the subject. I'm planning to build my own Faraday cage to shield my essential spare electronic items and I'm considering getting a really old Landrover Defender for this very reason (as well as being easy to repair in an economic crisis because parts are British made and commonly available). All modern cars require complex engine management systems and computer controlled electronic fuel injection. Older ones have virtually no electronics in them. Especially diesels.
The possibility of the power grid being destroyed by a solar storm like 1859 is also terrifying to me. Because its a matter of when and not if. It would take up to a decade to fix the power grid if something like this happened.