Herr finds the USPS fascinating: ubiquitous, relied on, and headed off a cliff. Its trucks are everywhere; few give it a second thought. “It’s one of those things that the public just takes for granted,” he says. “The mailman shows up, drops off the mail, and that’s it.”

He is struck by how many USPS executives started out as letter carriers or clerks. He finds them so consumed with delivering mail that they have been slow to grasp how swiftly the service’s financial condition is deteriorating. “We said, ‘What’s your 10-year plan?’ ” Herr recalls. “They didn’t have one.”

Congress gave him until the end of 2011 to report on the USPS’s woes. But Herr and his team concluded that the postal service’s business model was so badly broken that collapse was imminent. Abandoning a long tradition of overdue reports, they felt they had to deliver theirs 18 months early in April 2010 to the various House and Senate committees and subcommittees that watch over the USPS. A year later, the situation is even grimmer. With the rise of e-mail and the decline of letters, mail volume is falling at a staggering rate, and the postal service’s survival plan isn’t reassuring. Elsewhere in the world, postal services are grappling with the same dilemma—only most of them, in humbling contrast, are thriving.