Several folks have been, for years, advocating that the US government take the issue of national security seriously, and actively rebuild civil defense
When those Gawdless Rooshians collapsed, so did the Civil Defense network, at least here in Arkansas. I don't know how much of the funding was state and how much was Federal.
I haven't seen a radio with a "CD" mark since... I can't even remember. The library and county court house used to have shelters underneath, with 55-gallon drums of water and boxes of cots, bandages, and supplies. When they built a new library a few years ago, they hauled everything off to the dump. Helloo, people, there are still tornadoes and floods and earthquakes... but their focus was so narrowly on atomic armageddon the idea of having a chunk of town wiped clean by tornadoes (it's happened before) doesn't register.
Maybe they don't expect to deal with anything at a local level any more, and planning has turned into some sort of cargo cult where giant FEMA helicopters come swooping down loaded with goodies. Years ago when I was concerned about the disappearance of the shelters, the only answer I got was "we don't need those any more" and a selection of pitying looks.
There used to be Emergency Broadcast Signal ("this is only a test") tests on the radio. Those went away years ago; advertisers began using the EBS alert signal in ads, along with the usual crying babies, ringing telephones, beeping pagers, etc.
The only piece of the old Civil Defense system I know of that's still in operation (locally, anyway) are the air-raid sirens. They were going to take those down before they got reminded they're used to warn for tornadoes, too.
EMP will be the cheapest and most effective completely disabling thing they could use.
Maybe. There were no modern electronics back when above-ground testing stopped, which was right about the time discrete semiconductors were morphing into the first primitive integrated circuits.
There used to be a lot of EMP stuff up at [Only registered and activated users can see links. ], [Only registered and activated users can see links. ], and other places. The Fed had scanned a sizeable chunk of the declassified nuke stuff into .PDFs and put it online, but whole categories got yanked down within weeks after 11 Sept 2001. [searches] at least some of it is back up; go for it.
Most of the reports from Oak Ridge, Sandia, and Livermore are quite readable. There's even some Army stuff out there. I liked the reports of how they determined how close a nuke had to be to take out a pickup truck... instead of "modeling" a result, they just parked a bunch of trucks at different distances, popped a fiery mushroom, and then had some guys go out and see which ones would start and drive away.
EMP isn't easy to deal with. Just about any modern IC is vulnerable; the only question is how vulnerable.
One major issue is that an EMP bomb can be constructed cheaply with conventional explosives, some high-end capacitors, and a huge discharge coil. One foreign mag did a story on how easy it would be to construct a non-nuke EMP bomb. Many agencies have investigated how to make an EMP weapon; success or failure of these efforts is, obviously, classified.
If you're a survivalist, trade in that late-model computer-controlled vehicle and get something with an old-fashioned distributor, coil, and points. Hell, an old WW2 Jeep should do
Having spent my first ten years as an engineer in semiconductor, I can tell you that today's semi-conductors are actually more resitant to external spikes than they were originally. I was a test engineer and used to distructively test ICs. Before that I worked for a tester manufacturer and two of the customers that I dealt with were the NSA and Nuclear Effects Directorate. Pretty much all inputs and outputs have protection diodes on them that shunt current to ground over a certain voltage. You have to exceed the break down voltage of that diode and blow it open to get a surge inside. IC traces make pretty poor antenna's so you mostly need to protect it's power source from the surge. Use the shortest cord possible from your electronics to a surgeprotector and most of your electronics will survive.
The problem with the grid is that an EMP will trip substations and surge breakers all over the place. Probably every one on the grid would trip. Almost all of these require someone to go out and manually reset it. When the load goes away, power plants will go into emergency shutdown and need restarted. To restore the function of the grid, pieces will have to be re-enabled after appropriate generation capacity is back online. It will have to be done gradually. The farther away from generation you are, the longer you will be waiting. The entire US grid shuttingdown would suck because first the engineers would have to come up with a plan, which would be F'ed up by meddling from state and Federal officials trying to appease segments of the voting population. The longterm risks to the grid infrastructure come on start up when an unexpected surge could damage equipment in substations. Some of that equipment is one offs that take months to get from other countries since enviro laws and China pretty much killed that industry here.
The problem with modern vehicles is all that wiring acts as an antenna and you get voltage spikes in the wiring harness, which may get to something important like the engine control computer. There is an obscene amount of wiring in a modern car since we can't even roll our own windows down or lock our doors manually. Then again, it may not. I have two friends that had Dodge ram trucks who gto hit by lightning while driving them. Both strikes hit the antenna. One blew up the radio and nothing else. The other fried the engine computer and some sensors but strangely the radio still worked, but it still ran with the engine light on until he got home then wouldn't start again.
EMP effects are not uniform at all points with the same radius from the epicenter. The Earth's magnetic field strenght, terrain, atmospheric conditions, and compostion of the ground all affect how strong the effect is at a given spot. I don't think that we have ever actually set a bomb off at 50,000 feet so how that actually works out is anyones guess since all we have are computer models. I just assume that it will be bad like the simulations.