Yes, you need to register in advance in both places. However, SSNs are known to be fairly easy to use fradulently. Much more so than the UK's NI number, which is far better managed, tracked, and linked more closely to employment and social services. In the US, there have been many instances where the SSNs of dead people have been abused for a variety of reasons [1].
As to photo ID - there is no federal mandate to have photo ID for voting, and only 15 states require voters to show up to polls with a photo ID [2]. And those states that do are routinely accused by democrats of voter suppression for this requirement. That's kinda the point. One side argues that SSN verification is ripe for abuse, the other side argues that requiring ID is voter suppression.
In order to claim that the system is not ripe for abuse, I think you'd need to prove that SSNs are secure, which is gonna be a major problem because they are definitely not.
As to photo ID - there is no federal mandate to have photo ID for voting, and only 15 states require voters to show up to polls with a photo ID [2]. And those states that do are routinely accused by democrats of voter suppression for this requirement. That's kinda the point. One side argues that SSN verification is ripe for abuse, the other side argues that requiring ID is voter suppression.
In order to claim that the system is not ripe for abuse, I think you'd need to prove that SSNs are secure, which is gonna be a major problem because they are definitely not.
1: https://www.cnbc.com/2015/03/11/dead-peoples-social-security...
2: https://en.wikipedia.org/wiki/Voter_ID_laws_in_the_United_St...