UNITED FLIGHT 93

After the attacks, barriers and thigh-high cement bollards sprouted up seemingly overnight in Washington, D.C. But new threats show the need for adaptability.

Two fighter pilots scrambled into their F-16s on 9/11, knowing that it might be their last mission.

Two fighter pilots scrambled into their F-16s on 9/11, knowing that it might be their last mission.

Imagine coming into work one day like you normally do, but then later on, frantically embarking on a mission in which the success of it might result in your death.

Twenty years later, Jack Grandcolas remembers waking up at 7:03 that morning.

Thanks to the action of some very brave men, the world won’t ever know the additional destruction it could have seen on Sept. 11, 2001.

Mariah Mills (the biological daughter of Tom Burnett)The attacks happened when Mills was a junior in high school. Burnett and Mills’ birth mother dated in college and decided to give Mills up for adoption when she was born. Emmy GlickThe only child of Jeremy and Lyzbeth Glick, Emmy Glick wasn’t even 3 months old when her father died on United Flight 93. Now a junior in high school, Glick speaks to others on how to deal with tragedy. Morgan is a junior at Princeton High School, where she plays lacrosse.