https://www.theregister.co.uk/2017/10/04/white_house_plans_to_ditch_social_security_numbers_as_ids/

White House cybersecurity coordinator Rob Joyce has won the backing of Equifax's ex-CEO for a plan to stop using social security numbers as personal identifiers in the US.

We have no idea of Joyce's opinion of the endorsement, but what we do know is that he floated the notion in a speech given to a Washington Post-sponsored cybersecurity conference on Tuesday. Joyce suggested using a "modern cryptographic identifier" – presumably a hash or public-private key pair or something – to identify individual US taxpayers rather than the usual nine digits.