Watching the ongoing experiment in retroactive prognostication known as the 9/11 Commission, I keep trying to place events in their proper context. It is hard to think back that far, honestly to place oneself in that September-10th mindset. The events of 9/11 were profoundly life altering. The things that went on before seem trivial by comparison, in part because they were. Triviality was the essence of pre-9/11 political and social discourse. It was the legacy of the Clinton era, as frivolous a time in our history as can be remembered. Unfortunately, the growing terrorist threat was serious and our lack of focus played into their hands.

The al Qaeda attack plan exploited our preconceptions, particularly our knowledge of what a hijacking was. Before 9/11, hijacking was largely a form of theater. Hostage takings had become well-developed rituals. Killing was usually not the hijacker’s aim. Perhaps a hostage might be murdered by way of example, such as Leon Klinghoffer or Petty Officer Robert Dean Stethem. But most of the passengers were props, human shields to keep the terrorists alive during the negotiation phase. The way for innocents to get out of the situation alive was to relax, let the scene play out, and hope that if there is a rescue attempt, that none of the bad guys has a bomb. In short, cooperate, don’t escalate. Don’t be a hero.

This is why box cutters could be used successfully to hijack airliners. A box cutter isn’t a great weapon compared to a gun or a bomb, but could seriously cut up an unarmed passenger in a one-on-one struggle. And if it’s a matter of killing someone who is not expecting it, the box cutter is well suited for the task–as happened on at least one of the 9/11 flights. So it is understandable that most of the passengers on the doomed airliners took no action to save their lives. Why risk your life tangling with a maniac? But they did not know what was in store.

Would the box-cutter scenario work today? Of course not. We are no longer told to be quiescent and leave everything to the experts. Nor would we in any case. The risk is too great. The ritual has been shattered. If a man with a blade got up in an airplane and knifed someone, a human wave would descend on him, people armed with blankets, pillows, anything to turn the knife thrust; pens, pencils, something with a point; maybe laptops–you could seriously crack someone over the head if you landed the edge correctly; power cords–those bricks have some offensive value; food carts; anything that could be improvised to disable the terrorist. The sheer number of passengers would probably be sufficient; he would not be able to get enough cuts in before being taken down in a rush.

The difference between then and now is our depth of understanding. We now know what the enemy is capable of. We did not back then. Recall flight attendant Betty Ong’s calm assessment on American Flight 11, the plane that hit the north tower: “I don’t know, I think we’re getting hijacked.” Perhaps she did not understand what was going to happen up to the last. Maybe she did. Her colleague Amy Sweeney saw it in those final seconds–her last words were, “I see the water. I see the buildings. I see buildings… Oh, my God.” Two more aircraft hit their targets that day. But by the time United Flight 93 crashed in Pennsylvania the paradigm shift had been made. The admonition “Don’t be a hero” was replaced with “Let’s roll.” I suspect this change is permanent. No Americans will ever be led to slaughter that way again. The terrorists exploited a seam that they could only use once.

It is hard to admit we were simply taken by surprise, but we were. Al Qaeda pulled it off. Sometimes the unexpected happens–it is the nature of a surprise. It is fatuous to make the counterfactual argument that high-level decision makers “should have known” this kind of attack was coming. It was one of hundreds of possible threats from scores of terrorist groups. (Check out this 1997 vow to fly a Lear Jet full of explosives into the White House. It was not thought the most probable form of attack. It was not the most dangerous of the scenarios–certainly not compared to any of the “suitcase nuke” threats. And there was no reasonable way to have interdicted it given the lack of prior knowledge when, or where, or whether it was going to happen. It would have been great if we had known and had stopped it. Ironically, we would not have understood the magnitude of what we had achieved. “Suicide terrorists had planned to fly airliners into buildings? Those crazy bastards. What’s on ESPN?”

I disagree with Billy Wilder’s contention that hindsight is 20-20. Hindsight is a form of tunnel vision. It sees only one thing, a narrowly circumscribed version of the past, stripped of nuance, and bereft of the continuous sense of the unknown and unexpected that marks the unfolding of events. This is the fundamental contradiction that makes any product of this commission intellectually suspect. The commissioners will select the body of facts that will support their conclusions, based on the events as they happened; but they are unable to recapture our ignorance of the true and complete course of the future. The commissioners are looking into a single event that actually happened, but decision makers have to plan facing the more complex universe of future events that might happen. The commissioners know too much to be able to recreate the uncertainty of the period before September 11–or the certainties that turned out to be wrong. To paraphrase Bob Seger, if they didn’t know now what they didn’t know then, we might have a shot at the truth.