At least 21 plots to launch attacks on American soil have been thwarted. Here's a chronology.
After terrorist attacks, the 'last column' became a place where emergency responders and family members taped notes and photos of lost loved ones.
New York City's Osmond A. Church School adopted a curriculum approach that saved money by lowering teacher turnover and increasing collaboration.
Airlines move to reduce problems of 2007's dismal season, with a focus on New York area traffic.
America's JFK Airport is the 10th port of entry requiring noncitizen visitors to scan all 10 fingers.
The group's reputation has fallen in the Muslim world. But Western recruits who can more easily enter the US are being trained in Pakistan camps, intelligence officials say.