The first time, in 1993, despite the tragic loss of life and damage to the buildings, the towers remained standing, seemingly impregnable. The structural design had called for each tower's skin to be its main strength, through light glassandsteel facing threaded by steel columns. These columns gave the buildings their stiffness, while a cluster of central columns and steel trusses helped hold up each concrete floor. "Redundancy" is what the engineers call that structural backup which ensures a building's resilience, even if damaged-a word that also fit the WTC aesthetically and, now, historically. The twin towers were very strong, nothing compromised in the way of construction, an engineering tour de force; but no building, as we discovered, is meant to take the brunt f 'etliner gorged with jet fuel, shearing through its midsection. Whei jjj у collapsed, they fell straight down, not forward. Like the good soldier; were. MY FIRST INKLING of an attack on the Twin Towers came from a FedE: man He rang my doorbell around ninefifteen, and when I started to sigi for my package, he said, shaken, "Did you hear what happened? A plani crashed into the World Trade Center. You can see the black smoke fron here " Indeed, looking down Sackett Street in Brooklyn toward the rive on that infamously sunny day, I did see a plume of grayish black cloud a the end of my block. My first response was, So what? Planes do crash. A I went inside, the phone rang and it was my motherinlaw, telling me t( turn on the television. My motherinlaw is something of a TV addict especially if bad weather threatens; she'll keep the tube on just to track ; storm. I had been looking forward to a day of writing, now that my daugh ter Lily was beginning second grade, and so I said rather testily that couldn't turn on the television just now. But something urgent in her voici disturbed me, and so, against my usual practice, I did put on the TV in nr office, and saw rebroadcast footage of a second plane crashing into th< World Trade Center. Now I was gripped, shocked, queasy, as I realizec something unprecedented was happening. they Still, I wandered over by habit to my desktop computer, and tried t< punch in a few sentences. Maybe because I had been so fixated on this sub ject, I began to think the horrifying event was directly connected to thi geography of the waterfront: Manhattan's slender, elongated shape, sur rounded by rivers, made it easier for the hijacking pilots to hug the shon and spot the towers. My concentration, needless to say, was poor, but resisted giving myself up entirely to this (so it yet seemed) public event, am the kind of person who can write, and does, as a consoling escape fron anxiety, in the midst of carpenters, streetriveters, or other distractions Around tenthirty I was still writing with the television on, when my wife Cheryl, called me from Lily's Montessori school and said she was stickin| around, in case they decided to close and send the kids home.