When many of us recall the tragedy of Sept. 11, 2001, the horrible images of the World Trade Center twin towers collapsing is at the center of our minds. We also recall crashes at the Pentagon and in Pennsylvania.

But there were other events connected to that day that few of us realized until recently, with the publication of a new book, “The Only Plane in the Sky.” The author and historian Garrett Graff, who spoke at a recent book signing and reading at R.J. Julia in Madison, highlighted three historic occurrences for 9-11.

First, it was the largest maritime evacuation of people in recent history, including Dunkirk, with over 500,000 people removed by an armada of public and private boats, from the southern tip of Manhattan to the New Jersey shores. Some laws were broken and private boats borrowed to accomplish this movement.

Second, it was the responsibility of primarily one man, at his first day on the job, to facilitate the immediate landing “at the nearest field” of over 4,500 commercial and private aircraft flying over or coming into U.S. airspace, in an effort to clear the skies as fast as possible.

This feat was accomplished with few major problems, which then allowed military and air traffic controllers to monitor the president’s plane (“the only plane in the sky”) and any military aircraft needed for support.

Third, some military fighter aircraft were initially quickly launched without armament. Two planes were specifically ordered to intercept and bring down Flight 93 over Pennsylvania, thought to still be in the air. With no weapons, the pilots were on a suicide mission to actually crash their planes into the airliner.

They were saved by the brave passengers of Flight 93, who by fighting the terrorists on the plane forced it to crash.

I read the book prior to the Madison event. It is a very comprehensive story on the subject of the tragedy and events that occurred on that day 18 years ago. Graff spent many years compiling comments from more than 450 people on what they remembered. The action moves back and forth among the events as they were occurring, with the result that it was difficult to put the book down.

Graff noted the dramatic 17-minute period between the first North Tower crash, which many at the time thought just an accident, and the second South Tower crash, when we realized we were actually under attack.

This book serves as an important document for the quarter of our population who are age 18 and under and do not have a memory of that day, some of whom are now fighting in wars that started when they were babies.

We are reminded of the bombing of Pearl Harbor, where many military personnel were killed, caught off guard and trapped on boats. This was different. The “bombs” were our own commercial aircraft, used to attack civilians, piloted by men willing to die.

Most striking is the confusion created by an enemy who, quite literally, attacked us from inside our own country in a manner that we had never experienced and that we are still trying to completely understand. As one of my classmates, a professor of Tibetan religious studies, said 18 years ago: “We need to know why they hate us so much.”

Ed Johnson lives in Noank.