Connecticut State Police officers search outside St. Rose of Lima Roman Catholic Church in Newtown, Connecticut, on Sunday, December 16, after a threat prompted authorities to evacuate the building. Investigators found nothing to substantiate the reported threat, a police official said, declining to provide additional details. The church held Sunday services following last week's mass shooting at Sandy Hook Elementary School in Newtown.
Connecticut State Police officers walk out of St. Rose of Lima Roman Catholic Church after the Newtown church received a threat December 16.
Firefighters attach black bunting to a fire truck as a memorial at the fire station down the street from the Sandy Hook Elementary School in Newtown, Connecticut, on Saturday, December 15.
Connecticut Chief Medical Examiner H. Wayne Carver II talks to the media about the elementary school shooting during a press conference at Treadwell Memorial Park on December 15.
Zulma Sein is hugged by a family member outside of the entrance to the Sandy Hook School on Saturday.
Police officers keep guard at the entrance to the street leading to the Sandy Hook Elementary School on Saturday, December 15.
Connecticut State Police Lt. Paul Vance addresses the press on December 15.
Police officers stand at the entrance to the street leading to the Sandy Hook Elementary School on December 15.
Corinne McLaughlin, a student at the University of Hartford, bows her head during a candlelight vigil at Hartford, Connecticut's Bushnell Park on Friday, December 14, honoring the students and teachers who died at Sandy Hook Elementary School in nearby Newtown earlier in the day.
Distraught people leave the fire station after hearing news of their loved ones from officials on Friday.
Emergency workers stand in front of the Sandy Hook Elementary School in Newtown.
A child and her mother leave a staging area outside Sandy Hook Elementary School in Newtown, Connecticut, on December 14.
Members of the media converge on December 14 in front of an apartment at 1313 Grand Street in Hoboken, New Jersey. The apartment is believed to be connected to the Connecticut elementary school shooting.
Faisal Ali, right, of Colorado Springs, Colorado, joins other people outside the White House on December 14 to participate in a candlelight vigil to remember the victims of the Sandy Hook Elementary School shooting.
Connecticut State Police spokesman Lt. J. Paul Vance, center, briefs the media on the elementary school shootings during a press conference at Treadwell Memorial Park on December 14 in Newtown.
People weep and embrace near Sandy Hook Elementary School on Friday, December 14.
A woman leans on a man as she weeps near Sandy Hook Elementary School on December 14.
President Barack Obama wipes a tear as he speaks about the shooting at Sandy Hook Elementary School during a press briefing at the White House on December 14.
A woman weeps near the site of a shooting at Sandy Hook Elementary School on December 14.
A woman weeps near Sandy Hook Elementary School on December 14.
People comfort each other near Sandy Hook Elementary School on December 14.
A man takes in the scene near Sandy Hook Elementary School on December 14.
A young girl is given a blanket after being evacuated from Sandy Hook Elementary School on December 14.
State police personnel lead children from the school.
Children wait outside Sandy Hook Elementary School in Newtown, Connecticut, after the shooting.
A boy weeps at Reed Intermediate School after getting news of the shooting at Sandy Hook Elementary School on December 14.
FBI SWAT team members walk along Dickinson Drive near Sandy Hook Elementary School on December 14.
An aerial view of Sandy Hook Elementary School in Newtown, Connecticut on December 14.
Connecticut State Troopers arrive on the scene outside Sandy Hook Elementary School on December 14.
A Connecticut State Police officer runs with a shotgun at the Sandy Hook Elementary School in Newtown on December 14.
Police patrol the streets around Sandy Hook Elementary School on December 14.
People try to deal with the shock of the attack outside Sandy Hook Elementary School on December 14.
Connecticut State Police secure the scene of the shooting on December 14.
People embrace outside Sandy Hook Elementary School on December 14.
A man escorts his son away from Sandy Hook Elementary School on December 14.
People take in the news outside Sandy Hook Elementary School on December 14.
People line up to enter Newtown Methodist Church near the the scene of the shooting on December 14.
A woman speaks with a Connecticut state trooper outside Sandy Hook Elementary School on December 14.
The streets around Sandy Hook Elementary are packed with first responders and other vehicles.
A view of the scene at Sandy Hook Elementary School after the shooting.
A young boy is comforted outside Sandy Hook Elementary School on December 14.
People embrace each other on December 14.
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STORY HIGHLIGHTS
- Bob Greene describes parents' heartbreaking wait for kids, many of whom didn't arrive
- Greene: There are days we want to ask: Has America gone insane?
- He says the joke of duck-and-cover drills has given way to deadly serious lockdown drills
- Greene: We hear stories of attacks and what we should do, but it all feels like flailing
Editor's note: CNN contributor Bob Greene is a best-selling author whose 25 books include "Late Edition: A Love Story," "Once Upon a Town: The Miracle of the North Platte Canteen" and "When We Get to Surf City: A Journey Through America in Pursuit of Rock and Roll, Friendship, and Dreams."
(CNN) -- Taking attendance.
That is the phrase used by the parent of a Sandy Hook Elementary School student, describing to a reporter what went on in the firehouse near the school as terrified mothers and fathers arrived in the minutes and hours after the shootings.
The mothers and fathers looked anxiously for children who had lived through the shootings and had been brought into the firehouse. The surviving children and their parents found each other.
But the other parents waited and waited. Their sons and daughters did not appear.
And as the mothers and fathers who had been reunited with their children left the firehouse to go to their homes, a list began to be compiled. On it were the names of the boys and girls who were not accounted for.
Bob Greene
The most heart-shattering and unbearable list that can be imagined.
Those 20 children, as they had left home for school earlier that day, were boys and girls who had favorite television shows, and Christmas wish lists, and jokes that only they and their families understood, and brothers and sisters they knew they'd be having dinner with.
And parents, who now waited in the rapidly emptying Sandy Hook Volunteer Fire and Rescue station.
There are days when it seems fair to ask if part of American life has gone irretrievably insane. A description of the scene inside the elementary school, from a law enforcement official who spoke to a reporter, was that it resembled "a killing field."
That is a term of warfare, even of genocide, yet it seems not at all out of place in the context of contemporary domestic news.
"We have lockdown drills," said Mary Ann Jacob, a library clerk at the school. She was explaining to reporters that the teachers, children and staff at Sandy Hook Elementary, like teachers, children and staff at elementary schools all across the United States, were well versed in the advisability of preparing for a day like Friday.
Lockdown drills. More than half-a-century ago, children in elementary schools were trained in so-called duck-and-cover drills: the practice of diving under desks in case of nuclear attack by foreign enemies. Even at the time, it felt kind of comical; few boys and girls really believed that enemy aircraft were going to materialize over Midwestern or Southern or West Coast skies, bearing atomic payloads -- and a schoolroom desk, even in children's eyes, didn't promise much of a shelter against a bomb. American children tended to laugh and kid through the drills.
Today's enemies seem considerably more real, and the children are taught to understand that. "The kids knew the routine," the librarian said.
Thus, with the gunman in the school, she led the boys and girls to the lockdown-drill location: "between some bookcases and a wall, where you can't be seen from any windows."
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And, because they were children, and not soldiers trained in responding to heavy weaponry, when she and her colleagues then led the children to a storeroom and locked the door, she did the only thing she could to calm them as shots rang through the school:
Passed out crayons and paper.
We tend to talk about terrorism in terms of potential attacks from foreign shores, but on weekends like this one we have to acknowledge that the specter of terror seems to have become a part of the very atmosphere of American life. At a movie theater in Colorado, a shopping mall in Oregon, a school in a quiet Connecticut town ... the places change, the news media gather after the bloodshed, the police piece together the sequence of events, the grief counselors mobilize.
And somehow it all feels like flailing. At the end of a weekend like this one, do we feel at all secure that, having learned what we can about what has happened, the knowledge will help to prevent the next day and place of carnage? Of course not.
There is an old movie that is often played on television during the holiday season; its very title bears a message of warmth and safety and affectionate December memories. "Christmas in Connecticut," the movie is called, and the words are meant to comfort and cheer. It was broadcast again nationally late last week as America settled in for what is supposed to be a season of kindness and gentle spirit.
By the weekend in Connecticut, a law enforcement official, preparing to release the identities of the children who died, said that his colleagues were carefully compiling "a formal list of names, birthdates and information."
A resident of Newtown told a television reporter: "Things like this just aren't supposed to happen here."
No, they aren't. And "here" means not just Newtown, not just Connecticut, but this country we all share. It's not supposed to happen here.
Yet it does, again and again. And, in a season of peace, a strong, no-longer-young nation, blessed with so many people of compassion and wisdom and good will, finds itself in a bleak and familiar place -- unable to answer the most basic question of all:
Why?
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The opinions expressed in this commentary are solely those of Bob Greene.