With our allies, we assume their virtues show who they really are, while their failures are only slips, distortions, or masks.
With our opponents, we reverse it – their good deeds are dismissed as fake or manipulative, while their mistakes and vices are taken as proof of their true character.
This double standard shows that the rule isn’t actually “goodness is authenticity”, the rule is “the kind of goodness I value is authenticity.”