I helped deploy a Verisign affiliate in Australia that had planned to do just that. I believe the post office was going to be the registration authority to vet

I helped deploy a Verisign affiliate in Australia that had planned to do just that. I believe the post office was going to be the registration authority to vet users identity, and then there was going be some mechanism to issue a subscriber certificate from there, maybe on a smart card. This was 20 years ago, no idea how far it got. The physical security they built into the facility housing the root CA was pretty intense.