In the post-9/11 world, the United States is paying attention to security at home more than ever before, including creating a new government agency to specifically deal with homeland security. • N.Y. subway threat possibly hoax
• Penn Station searched after terror warning
• White House releases list of 10 foiled attacks
• U.S. cities increase security after London blasts
• 'High risk' of WMD attack in decade
• Graphic: U.S. intelligence structure
• Uncertain state of security | On alert in the skies | On the rails
• Interactive: Terror alert levels | Explainer: Alert system • Airport security 'fast lane' to lapse
• CNN probe finds weak link in air security
• Report: Airport screeners lack training
• Precautions: What you can do
• America Prepared Campaign  | Ready.gov  • 9/11 commissioners cite aviation security gaps
• 9/11 report: 'We must act' | Gallery: Key testimony
• Flight 93 hijacker: 'Shall we finish it off?
• Audio Slide Show: Reactions and recommendations
• The full report | Gallery: 9/11 Commission