Looks like North Korea has an ICBM. If they put a thermonuclear warhead on it, then North Korea could do an EMP (Electro Magnetic Propulsion) attack above the U.S. that would knock out the entire electrical grid system.
It would not matter if your electronics are plugged in or not. They would all be destroyed. It would take years to rebuild it.
Within a 7 days all the food in the grocery stores would go bad. Within 3 to 4 weeks there would be chaos in the streets. Certainly in the cities. They would be death traps. P
Hopefully, measurements are being accelerated to protect the grid. It is my understanding that this is taking place per President Trump order. President Obama never did it.
“could do an EMP (Electro Magnetic Propulsion) attack above the U.S. that would knock out the entire electrical grid system.”
The size of bomb needed to knock out the ENTIRE US electrical grid... yeah, no freaking way. This country is a lot bigger than you think.
“It would not matter if your electronics are plugged in or not. They would all be destroyed.”
A 1 megaton blast at 200,000 km altitude (sweet spot in Ionosphere for EMP effects) would generate ~~ 4.2 *10^15 joules at that point which might translate to ~~ 6.5 Megawatts/200,000 meters on the surface directly beneath the blast, distributed horizon to horizon (~~ 1,200 miles of Earth surface in every direction) so electronics on the surface directly beneath the blast would see an electrical surge from the Hall effect of a magnetic wave passing through conductive surfaces/wire of about 324 watts/square meter.
Obviously the longer length of your wire (circuitry) that is exposed to the EMP the greater your total wattage from the surge will be in your circuit.
Telephone wires could easily spark. Your headlights/taillights might glow bright for a moment, perhaps even pop. Parallel circuits will be less taxed than series circuits.
...but the surge directly below the blast will be orders of magnitude greater than the final EMP that reaches the blast’s 1,200 mile horizon radius (1,931 Km).
Distance matters.
6.5 Megawatts divided by 1,931,000 meters means that the EMP on the end horizon of the blast is only ~~ 3.37 watts per square meter. Pretty much every circuit made can handle that “surge”.
324 watts/sq meter directly under a high-altitude Space EMP blast, trailing down to 3.37 watts/sq meter 1,200 miles horizontally away from the EMP blast.
EMP = Electro-Magnetic Pulse.
Just a small detail.