the locker room: Am I true
They were the age staring down the barrel not of Is anything true but of Am I true, of What am I, of What is this thing, and it made them strange.
Context
The narrator's aside on the towel-snapping 16s converts the epistemological question into an existential one, and the shift is the theme's private center. The children have moved past "Is anything true" (Possalthwaite's just-discovered nihilism) to "Am I true, of What am I" — authenticity turned inward, the self as the thing whose truth is now in doubt. It's the register-war relocated to identity: not "can I trust what's said to me" but "is there a real me under the performances," the question that makes the age "strange." The line quietly names what the whole anthology circles — that irony's corrosion doesn't stop at the world's claims but reaches the self's, and the terror isn't a false statement but a possibly-false person.