The smell of hot popcorn drifted upward from the concourse below, lingering in the warm Californian air like an atmospheric irony, and a Jumbotron directly in front of me displayed a blandly handsome announcer seated behind a curved desk emblazoned with DARPA’s logo: a sports broadcast mise-en-scène from some speculative future, vaguely fascist, in which the machinery of national defense had become a spectacle of mass entertainment.