In an unmarked building in downtown Washington, Brian K. Nagel and 15 other Secret Service agents manned a high-tech command center, poised for the largest-ever roundup of a cybercrime gang. A huge map of the U.S., spread across 12 digital screens, gave them a view of their prey, from Arizona to New Jersey. It was Tuesday, Oct. 26, 2004, and Operation Firewall was about to be unleashed…
