Questions also persist about Giuliani on the day itself. As Wayne Barrett, a Giuliani biographer, has pointed out, the very images themselves of the mayor’s trekking through apocalyptic ash in lower Manhattan suggest a Giuliani blunder: placing the city’s emergency command center in the World Trade Center, already a known terrorist target. (Giuliani later admitted the command center’s location was poorly chosen.) Had the center been placed in a lower-profile location, the city’s emergency infrastructure might not have been so crippled in the hours after the attacks.

But Giuliani may well prove a tougher target than John Kerry. Before the Swift Boat Veterans for Truth launched their attack on Kerry’s Vietnam record in August 2004, most Americans had only a vague sense of his bio, leaving him susceptible to a counternarrative. But the image of Giuliani as 9/11 hero, as the voice of resolve when all other authority was absent, is deeply ingrained in the American consciousness. The real danger for Giuliani may well be not a campaign focused around his role on his 9/11 performance, but a campaign focused on anything else.