I'd say "effectively" is doing the heavy lifting here. Which is to say, we could undo that database if we wanted to. If society decided it collectively hated S

I'd say "effectively" is doing the heavy lifting here. Which is to say, we could undo that database if we wanted to. If society decided it collectively hated SSNs, the work to obscure that system, or to poison that well, would be far easier than with irises.