So there was recently a massive power outage to a significant portion of South America, mostly in Argentina, Uruguay and Paraguay. Surely there were bitcoin nodes running in these countries. I've always been curious about the effect of, for example, a massive EMP on the network. Does anyone have any links that can help visualize the effect of a large amount of miners going offline and then rejoining the network? At what point would something like this screw up the blockchain by fragmenting the network?
After a little searching it looks like there are an insignificant number of nodes running in those countries, but what effect would an EMP over say the US and Germany at the same time have on the network?