blocks can be broadcast over any communications medium. the shared state of the ledger would be smuggled in via any means necessary, from radio to messenger pigeon.

this remains true if retail payments migrate to second layer solutions. the important thing is sharing the same base layer anchor.

block confirmations would have to increase to mitigate the likely orphaning of chains coming out of different zones.

it's a good example of why achieving its civilisational infrastructure goals requires lightweight blocks.