Mary Marshall Clark, Director of the Center for Oral History Research at Columbia University, and the driving force behind the September 11th Oral Histories Project, talks about how 9/11 exists in the minds of those who lived through it, as told to her through thousands of hours of oral histories.

Sad to realize a generation never knew the tranquil world existed before #September11th. I’m not sure we can ever convey the horrors we witnessed that day, in part because they’ve never know the sense of safety we took for granted before the attacks.

— Albert Fox Cahn (@CahnLawNY) September 11, 2019

I watched the jet hit the Pentagon/sister was stuck in Manhattan. We fell completely into the terrorists trap: we overreacted, we betrayed our "values", we violated untold norms laws we have accepted an unprecedented surveillance state.

— (((Nathan))) (@ntableman) September 11, 2019

Caller Matthew was 13 on 9/11. His father was killed."My teacher brought me to the office to tell me... my father worked on 104th floor.""Today I drove my 4 y/o son to school. He's named Joseph, after my father. It's remarkable to see happiness... It's been a long journey. "

— Brian Lehrer Show (@BrianLehrer) September 11, 2019

Adjunct professor at Baruch college decided not to hold class on her birthday, so many of her students went to work (at the WTC). She lost 11 students that day.She doesn't celebrate her birthday anymore, but her son recently told her "It was your birthday first."

— Brian Lehrer Show (@BrianLehrer) September 11, 2019