A veteran CIA operative scrutinizes Homeland Security--including the preparedness of military installations, rail systems, chemical plants, and dams--and finds that America is still vulnerable to its enemies.

Every day in Washington, DC, the blue-and-gold 1st Helicopter Squadron, codenamed "MUSSEL," flies over the Potomac River. As obvious as the Presidential motorcade, most people assume the squadron is a travel perk for VIPs. They're only half right: while the helicopters do provide transport, the unit exists to evacuate high-ranking officials in the event of a terrorist or nuclear attack on the capital. In the event of an attack, select officials would...