Thirteen years have passed since the attack on New York City and Washington, DC by Islamic terrorists.

I was a junior in high school at the time. I remember exactly where I was on the road when I heard on the radio that a plane had hit the World Trade Center in New York. I thought it was pretty odd, but the details were light, and in my mind I chalked it up to an accident involving a small aircraft.

By the time I made it to my first-hour class, that was clearly not the case. More planes hijacked, more crashes, more death.

The day was a blur of sorts; in only one class did we actually focus on schoolwork (math). For the most part, we listened to the news, talked quietly, prayed.

I also remember, late that night, crawling into bed and wondering if perhaps the whole thing had been some fevered nightmare. Maybe I would wake up the next morning, it would be September 11th, and no great tragedy had occurred, some 3000 American lives had not been lost.

I was wrong.

My wife has told me once that September 11th makes her feel old. Not because she’s particularly old – she’s two years younger than I am, and I haven’t even hit 30 yet. No, she feels old because of her students at the high school. For those of us who are old enough to have clear memory, there was a “before” and “after” – and the “after” made the world seem much darker and more dangerous. Illusions were destroyed, veils cast down – there was no denying there is plain evil in the world.

For those kids, though, there’s not really a “before”. They don’t have a concept of how the world changed for Americans on September 11th, 2001.

But it’s also important not to get caught up in the past. The world continues to spin on, and we can’t afford to be endlessly caught in the immediate aftermath of an attack thirteen years ago. It’s not healthy to fixate on a single point in time, and not allow growth, context, and understanding.

In the months following 9/11/01, many Americans would have rejoiced had Osama Bin Laden been immediately found and shot by American forces. But by the time the SEALs caught up with him and put a bullet in his brain close to a decade later, I couldn’t find any note of celebration in myself, because it wouldn’t make a difference. The fighting would go on, the terrorism would continue, the Middle East would continue in its terse infighting. There was no closure.

Never forget, but move on as well – the world keeps spinning.