But his colleagues, who also worked that day, and who were part of the team that responded by notifying US military authorities and closing US air space, bringing hundreds of passenger jets to a quick, safe landing, also remember vividly what happened. Gradually, the anguish occasioned by the memories of that day has subsided, but the mark remains.
There is anger at the persistent conspiracy theories about why military jets weren't scrambled sooner. There is pride at having overcome tremendous logistical hurdles to get other airliners out of the air and at having done all they could to foil the hijackers. And there is sadness that their efforts were not enough.
“I was very proud, intensely proud of my coworkers and the entire aviation community, the pilots, what they had done to secure the nation’s airspace so quickly,” says Tom Roberts. “It was a proud moment, but at same time bittersweet because of the loss of life. That’s the way it still is for me.”
On Sept. 11, Mr. Roberts was at his screen working a nearby sector of air space that Flight 11 was supposed to traverse over Albany, N.Y. But the flight did not show up, and he soon realized a major crisis was emerging.