that puts a pretty big footprint on the ground out of commission as far as electronics and power is concerned, say 500 mile diameter.
I agree though that the Carrington event, the solar flare, is far more serious because it could affect the whole planet or a big part of it.
yes, that's a FOBS system. In a way, it's worse. The 14 minute DEW alert is based on ICBM's which have a much higher and longer orbit. Against a FOBS attack, the interval to decide NOT to launch a retaliatory strike (which is the way the response is structured) is MUCH smaller. Maybe five minutes.
My biggest point on this, other than the irrelevancy of bitcoin or any other currency, is that in the interval between launch and response, there is literally no way to determine whether that missile is aimed to launch an attack against electronics or kill a city.
In terms of financial devastation, a monster solar flare is probably more of a concern as it's effects would be at least half the globe, depending on duration. But other than creating chaos, it would hardly be a world stopping event. Any fool who thinks they can pull off an EMP strike without direct nuclear reprisal just hasn't done the math. Unfortunately, a whole hell of a lot of politicians on all sides aren't too good about the math. By some strange fortune, none of the real looney-tunes have gotten hold of the launch codes yet.
Of all the nuclear powers on earth, I fear North Korea the least, because they have such primitive delivery systems. Our warning against them would be pretty good, unless they tried to pull off a FOBS attack from a boat, and frankly I think China would then erase them from the map before anyone else responded. I also think that the current "dear leader" is young, but not stupid. He knows this. They are playing a game of brinkmanship and it will end badly, but probably not horribly from a global standpoing. China is unlikely to use their nukes as anything but a deterrent. Russia and the USA likewise, unless McCain somehow gets hold of the launch codes. India probably falls in that category. That basically leaves two major wildcards. Pakistan and Israel. Pakistan is much like North Korea in that respect, so probably less of a threat than most, except for their love of pissing off India. Israel is the nuclear power than frightens me the most.
Israel has never openly admitted to having a nuclear arsenal and are not signatory to the non proliferation agreements. They have hinted, more than once, that they would be willing to use nukes against their neighbors. That they do have them, and what numbers, is an open secret. Their arsenal is not huge, but they could absolutely devastate much of the middle east. They could also easily reach Russia and China, and a great deal of Africa. This is not even counting their submarines. In my view, the only thing that restrains them is that they are not suicidal, for the most part. But they do have itchy trigger fingers.
Despite a great deal of chest pounding by the bastards that rule my country, Iran is not a threat. Even if they could or have developed some small scale weapons, they have no real way to deliver them against anyone but their neighbors. And they are painfully aware of how easy it would be for Israel to remove them from the map with their large and modern nuclear arsenal.
I have been and remain a proponent of nuclear electric power, but the bomb needs to go. Somehow, we as a species need to figure out a way to put an end to the existence of these weapons. They serve NO military purpose. They are and always have been a purely political terror weapon. While in a given area, poison gas has a longer and more devastating effect, there's no chance of such weapons ever going global, and mitigation is trivial by comparison.
Given the larger picture, I see any worry about whether a currency, whatever it's merits, might survive a nuclear attack to be insultingly trivial.