Only an EMP black-out is permanent and on a larger scale... How?
I mean, okay, so if an EMP hits the grand ole U.S. of A. What's stopping U.S. Nuclear Powered Aircraft Carriers and Submarines from returning to assist, firstly by giving power to a factory to rebuild all the circuitry to get the grid back up and running. After all, an EMP can't destroy circuits that haven't been created yet.
And plunge America into Silence and Darkness
I'm pretty sure the well-armed public of America will adapt to candles and kerosene burners pretty quickly, not to mention Solar Powered Generators like HANS. Then if you have a generator, all you need is an Ecoloblue Unit for pure drinking water for the whole family.
Nobody will be looting homes for Electronic/Tech goods, most of the looting will be from the supermarkets who have food left. But I believe Americans would pull together in an event such as this.
One blast will reduce our army to fighting using weapons that existed before the 1900s...
I mean come on, I'm sure the world would have been a completely different place if AK-47's, M-16's, AR-15's along with all the grenades and shoulder holstered missile launchers were available back then. I'm guessing A.I. would take a serious hit, so would Tesla, pornography might get a bit stale, cryptocurrency will be worth piss, dopamine addictions may go into remission and obesity will disappear over time.
CommUNITY is what it's all about in the end.