Both of these! And spot on with (mutual) motive analysis to come up with an "alignment" matrix.

I was inspired some time ago by Stella Rimington's writing (ex MI5 chief) that "identity" is actually a very poor basis for trust and authentication. It's unnerving watching the whole zero-trust show organise itself around notions of strong identity (as opposed to role and earned trust), which might turn out to be a rather silly thing to do.