"Gain unprecedented access to the building nerve center of the U.S. military as National Geographic takes you deep inside the Pentagon. Enter restricted areas, including a Joint Chiefs of Staff meeting in the high security room known as "The Tank." Learn the intriguing history from those who know it best and witness America's offense in the war against terrorism. It's a fascinating, intimate view of the Pentagon's triumphs, defeats, and challenges."-- From publisher.

Special features : Photo gallery ; Pentagon timeline ; Recommended Programs ; Experience National Geographic. Documentary.

Introduction -- U.S. defense -- 21st century warfare -- The Pentagon community -- The attack of Sept 11th -- Original construction -- The Pentagon's mission -- The Pentagon staff -- The wartime Pentagon -- Homeland Security -- New safety measures -- The Phoenix Project -- New approach to war -- Weapons of war.