This from Gary Wolf at Wired:

Fortunately, this advice was mostly ignored. According to the engineers, use of elevators in the early phase of the evacuation, along with the decision to not stay put, saved roughly 2,500 lives. This disobedience had nothing to do with panic. The report documents how evacuees stopped to help the injured and assist the mobility-impaired, even to give emotional comfort. Not panic but what disaster experts call reasoned flight ruled the day.

In fact, the people inside the towers were better informed and far more knowledgeable than emergency operators far from the scene. While walking down the stairs, they answered their cell phones and glanced at their BlackBerries, learning from friends that there had been a terrorist attack and that the Pentagon had also been hit. News of what was happening passed by word of mouth, and fellow workers pressed hesitating colleagues to continue their exit.

We know that US borders are porous, that major targets are largely undefended, and that the multicolor threat alert scheme known affectionately as “the rainbow of doom” is a national joke. Anybody who has been paying attention probably suspects that if we rely on orders from above to protect us, we’ll be in terrible shape. But in a networked era, we have increasing opportunities to help ourselves. This is the real source of homeland security: not authoritarian schemes of surveillance and punishment, but multichannel networks of advice, information, and mutual aid.

Remain vigilant

Via InstaPundit