By Thomas L. Friedman, New York Times

Looking at scenes of the Boston sidewalk a few hours after Monday’s bombing — torn clothing, bloodstains, shards of glass — I found my mind going back to a similar sidewalk in Tel Aviv in September 2003. A Hamas suicide bomber had blown himself up at a bus stop outside the Tsrifin army base, and by coincidence I was nearby and got there to witness the immediate aftermath. As I wrote then, parts of the bomber were still on the street, including his hairy leg. His shoe had been blown off, but his brown sock was still daintily on his foot. Israeli rescue workers calmly carried away the dead on stretchers, with an odd mix of horror and routine. But what I remember most was something the police spokesman said to me: “We will have this whole area cleaned up in two hours. By morning, the bus stop will be repaired. You will never know this happened.”

Thomas L. Friedman

We still do not know who set off the Boston Marathon bombs or why. But we do know now, after 9/11, after all the terrorism the world has seen in the last decade, what the right reaction is: wash the sidewalk, wipe away the blood, and let whoever did it know that while they have sickeningly maimed and killed some of our brothers and sisters, they have left no trace on our society or way of life. Terrorists are not strong enough to do that — only we can do that to ourselves — and we must never accommodate them.

So let’s repair the sidewalk immediately, fix the windows, fill the holes and leave no trace — no shrines, no flowers, no statues, no plaques — and return life to normal there as fast as possible. Let’s defy the terrorists, by not allowing them to leave even the smallest scar on our streets, and honor the dead by sanctifying our values, by affirming life and all those things that make us stronger and bring us closer together as a country.

Let’s name a playground or a school after that 8-year-old boy, Martin Richard, who was standing by the finish line, and who ran out and hugged his father, Bill, after he completed the race, and then trustingly walked back to the sidewalk to be with his mother and sister when the bomb tore through them all. Let’s donate to the favorite life-giving charities of the other victims. Let’s pitch in to help the injured recover. But on lovely Boylston Street in Boston, a place normally so full of life, let there be no reminder whatsoever of what President Obama called this “heinous and cowardly act” of terror.

And while we are at it, let’s schedule another Boston Marathon as soon as possible. Cave dwelling is for terrorists. Americans? We run in the open on our streets — men and women, young and old, new immigrants and foreigners, in shorts not armor, with abandon and never fear, eyes always on the prize, never on all those “suspicious” bundles on the curb. In today’s world, sometimes we pay for that quintessentially American naïveté, but the benefits — living in an open society — always outweigh the costs.

Terrorists know that, of course, and feed on it. The explosives were reportedly packed into six-liter pressure cookers, tucked into black duffel bags and then left on the ground. That is the signature of modern terrorism: to turn routine items from our lives into bombs: the shoe, the backpack, the car, the airplane, the cellphone, the laptop, the garage door opener, fertilizer, the printer, the pressure cooker — so that everything and everyone becomes a source of suspicion.

This can pose a much greater threat to our open society than the Soviet Red Army ever did — if we let it — because this kind of terrorism attacks the essential thing that keeps an open society open: trust. Trust is built into every aspect, every building, every interaction and every marathon in our open society. Terrorists can steal it for a moment or even a while, but we dare not let them fundamentally erode it, and I don’t think we will. When you watch the video of the bombing aftermath, notice how many people you see running toward the blast within seconds to help, even though more bombs easily could have been set to explode there.

Fortunately, we don’t frighten easily anymore. You could feel it in the country on Tuesday morning. We’ve been through 9/11. We probably overreacted then, but never again. We tracked down Osama bin Laden with police and intelligence work, and we’ll do the same in this case. But meanwhile, even in this age of terrorism, let’s keep heeding the advice of an advertisement that you could see hanging in a Boylston Street window in a picture taken after the blast. The picture showed a marathoner sifting through unclaimed runners’ bags left behind after the explosion. Behind him, in the window, the ad poster says: “Your home should be a place to rest easy.”

Only we can take that away from ourselves — not some terrorist with one despicable spasm of madness. So hug your kids tonight, but also encourage them to start training for the next marathon tomorrow. Now that I think of it, maybe we should make this one longer — from Boston to the site of the World Trade Center to the Pentagon — to remind ourselves and anyone else who needs reminding: This is our house. We intend to relax here. And we are not afraid.