I'm thinking establishing a pre-determined amateur radio frequency might be a better idea, since travel might not be an option for a lot of people, and it might not even be safe.

You don't need a license to purchase an amateur radio, just to broadcast on it. However, there is an exception to that rule that says anyone may broadcast on any frequency in the event of an emergency. I think the collapse of civilization as we know it qualifies.

Any other hams out there want to chime in on this?