Bitcoin can run on fm transmitters, Bluetooth, nostr probably can too.
Everyone's a genius until someone finds another way...
Discussion
It can but you'll somehow have to connect the whole world without missing anybody. If a region gets desyncs from the network it is over for the bitcoin. To be viable you'll also have to do it in a cheap way so anyone can get it without spending 100s of dollars.
The network will.adapt. the whole world might become a LAN
Have you heard of blockkstream satellites?
Yes, I have. It is too expensive for most people to get.
Also "will adapt" isn't viable sollution. We need something rn so we can start using it whenever a government starts to act bad. Not start thinking a sollutions after the internet has been stopped.
Another problem I am thinking of is extreamly high fees. Since I don't think how lightning can work over satelite or whatever the tech used is. There won't be as many miners and too many transactions.
A few dozen blockstream stations around the world would be enough to keep anything like this from happening. And there are probably way more than that around already.
The problem of no internet still exists. Also that pretty much centralizes the network since blockstream is the only provider of the blockchain
Bmockstream stations will connect to LANs.
They will all be providers of the blockchain, keeping it decentralized.
Blockstream would be the bridge in this extreme situation.