My father hadn’t heard the news. I asked him to stay home, but he said my mother was out of her favorite cereal, so he might have to make a trip to the store. Dad is an avid frequenter of discount supermarkets. One of his favorites is Shoppers Food Warehouse. The first murder was outside that store — though not the branch he goes to.

"Mom can do without her cereal for one day," I said. "Please stay inside."

"Well," he said, "we’ll see. But I really don’t think anything could happen."

I called my sister, who lives in Montgomery County and has three school-age kids. All of the county’s schools were locked down by then. When I told her about Dad, she said, "That’s crazy — he’s not going out. I’ll call him."

A few hours later, Dad called me. Mom wanted to go for a walk — would I talk to her? By then he must have listened to enough news to be anxious himself.

He and my mother live in a quiet subdivision where, to my knowledge, no murder or violent attack has ever taken place. Mom doesn’t drive anymore, and she looks forward to her walks — two or three a day. After much back and forth, I convinced her to stay in.

"Just for today," I said. "We’re all trying to be careful."

The next day, they were back to their routines: Dad going to the store, Mom walking in the neighborhood. By then I didn’t object. They can’t stay inside all day. No one can.

Public events always get filtered through a personal prism. A year ago, the terrorist attacks receded to the background of a family crisis for me. On Sept. 11, my mother was hospitalized for a serious illness. That morning on the office TV, I watched the World Trade Center collapse and got my first sight of the destruction at the Pentagon. That night, I slept in a recliner by Mom’s bed.

For the next five days, I got much of my terrorism news from her roommate’s running commentary on the other side of the curtain ("These folks are going to have lung problems for years, I’m telling you"); from half-heard doses of NPR between hospital and home, home and work, work and hospital; from snippets of Nightline as I brushed my teeth when another family member had bedside duty. I somehow managed to miss the redemption of Rudy Giuliani entirely. A week or so after the attacks, when I heard how valiant he’d been, I thought: Really? Giuliani? Where was I?

It was only on Sept. 13 that I remembered to call my best friend from college, who I suddenly had a sinking feeling had worked in the Twin Towers, though I wasn’t sure. He had, and he was OK — he hadn’t been at the office on the 11th. We chatted for a few minutes, a little awkwardly. I had a legitimate reason for forgetting, but I still feel guilty that I didn’t check in with him sooner.

My mother recovered. For a good while, the whole country was extra careful. Then most of us started flying again — maybe saying a prayer at takeoff, but flying.

A neighbor of mine spent last weekend in West Virginia — where none of the sniper attacks had been — and she says people were filling their tanks from a crouching position. The Guardian Angels are manning pumps around town. But besides posting police reinforcements outside schools and continuing the lockdown — both of which add needed security and reassure children and parents — I don’t know what precautions can really protect us. After all, none of the victims were being reckless. They were shopping, mowing the lawn, reading on a bench. And how can you keep an eye out for a shooter who may be hundreds of yards away?

People have been asking me, as they did after the attack on the Pentagon, "How are you holding up?" I’m always a little embarrassed when I say, "Pretty well." It’s not that I don’t care or worry. It’s just that there’s a powerlessness, and it’s more pervasive than either care or worry. Yes, it’s a burden, but paradoxically, it’s also what allows me to keep going from day to day.