Comment by lxgr
The problem wouldn’t be a lack of alternative means to facilitate transactions, it would be a lack of trusted counterparties to transact with.
Grocery stores and bars used to let local trusted customers pay their accumulated purchases once per week or month, or accept personal checks from them without any means of verifying whether they were covered.
Today? It’s essentially cash or credit card, and no more mechanisms for local/decentralized credit decisions whatsoever, even if a checkout clerk might personally know a customer.
Because of ubiquitous connectivity, we have greatly increased, but also centralized trust. Local trust isn’t restored quickly, especially during an emergency when tensions are high anyway.
There are digital forms of currency already but barring that, you can still manage centralized trust with distributed communication.
Ie: maybe I trust a mechanism by Google/Apple where tap becomes powered locally and the phone/device itself carries a balance.
It’s true that these solutions don’t exist today but they are not far away with the amount of pressure we are talking about by losing the internet.
Also, credit cards used to work in a similar way to checks. The information would be recorded and the transaction would be finalized later.
I came across a pre-magnetic-strip credit card years ago… it’s pretty fascinating how currency has evolved in the last half-century. There is no reason for me to think that it will stop where we are at today.