No power = no cell coverage
Landlines are a thing of the past and for the most part that means that people lack the ability to call for help beyond your basic 911 service.
So we’ve effectively tied two pieces of critical infrastructure together and made one dependent upon the other.
That needs to be addressed and resolved.
Worse: POTS and ISDN landlines are getting shut down left and right (at least in Germany, probably also in the US) as there are simply no linecard manufacturers remaining. Everything is switched to CPE-terminated VoIP crap (ever tried sending a fax with a fax machine linked on a consumer VoIP circuit?). So even if you HAVE a landline, its usability for 911 depends on the DSLAM having backup power (which many only have for 24-48h).
Amateur radio license: if my wife can pass the test, anyone on HN ought to be able to.
The risk profile as of a month or so ago now includes short-notice extended multiple-day intentional power-outs from the utility service itself.