Even as we struggle to figure out what happened at Sandy Hook Elementary School -- who did what and why -- the sad frequency of attacks by men with guns is creating a growing school of thought based on a simple premise: Be ready for the bullets. These mass shootings, but also bombings and terror attacks, have fueled a need, rational or not, to be prepared for the worst in whatever form it may come and know how to act when it does.
The city of Houston, one of the nation's largest, has even produced a video advising residents of what to do should they encounter an "active shooter." It is called "Run. Hide. Fight." and was released in the day after a gunman opened fire in July at a midnight "Batman" movie screening in Aurora, Colo., killing 12 people.
After a spate of school shootings that included the 1999 Columbine massacre in Colorado and the 2007 shooting at Virginia Tech, schools heightened security, developed new guidelines for spotting potentially threatening individuals and implemented so-called "lockdown drills" to better help students know what to do in the event of an emergency.
And with Sandy Hook, it seems to have marched forward: Have we gone so far down this rabbit hole of mass murder in America that we must make sure our first-graders are ready with escape routes, too?
The response inside the school, authorities said, seemed to be a mix of the two notions of preparation and instinct -- as teachers, a school psychologist, a principal risked, and in some cases lost, their lives to protect the children in their care.
Lockdown drills were part of the routine for the nearly 450 kindergartners through fourth-graders who attended Sandy Hook. Earlier this year, principal Dawn Hochsprung tweeted a picture of an evacuation exercise, showing little ones bundled in winter coats standing outside the school, quietly in line behind their teachers. Hochsprung died Friday at the gunman's hand.
And while nothing can ever prepare children for what happened at Sandy Hook, having a specific procedure to follow probably did help keep the youngsters calm and focused -- and could potentially minimize the effects of the trauma down the road, said Stephen Brock, a professor of school psychology at California State University, Sacramento.
He recalled in recent days hearing a little girl in Connecticut on the radio "talking about how the teacher told them to go to the corner of the room away from the doors and windows so the animal couldn't get in."
"In her mind, it was probably a ... lion or a tiger," Brock said. Nevertheless, "they followed procedures that they had been drilled in before. By responding appropriately, it can make the situation appear less threatening if there's something that they can do to keep themselves safe."
Not unlike adult survivors of these awful tragedies, children also have their own innate tendencies that help influence their response. Even if they can't make their own decisions to hide or escape -- they know instinctively who can: the adults around them, to whom they look for cues about how to behave.
Think of a child at a park who falls off the swing set, Brock said. If they look over at Mom and she's upset, chances are the child will get upset, too. If not, "They'd wipe ... off their knee and go out and play some more," he said. "Young kids are going to have their threat perception significantly dictated by how the adults around them are behaving."
Without their moms or dads to look to, the schoolchildren at Sandy Hook turned to their teachers for those cues. And those teachers, in turn, became their saviors and heroes.
In the school library, clerk Mary Ann Jacob was working with a group of 18 fourth-graders when she heard a commotion over the school intercom. She called down to the main office and was told, "There's a shooting. Then she yelled "lock down" to her students before running across the hall to another classroom to tell them to lock down, as well.
"The kids know the routine, and the teachers know the routine, and everyone has a spot in their room where they're supposed to go to," she told reporters on the scene.
Eventually Jacob and three other adults ushered the children into a storage room and locked the door. They found crayons and paper, which they divvied up among the kids.
"They were asking, 'What's going on?' We said, 'We don't know. Our job is to stay quiet. It may be a drill. It may not. But we're just going to stay here.'"
Jacob, of course, knew that it was no drill.
As soon as she heard the shots, first-grade teacher Kaitlin Roig rushed her 15 students into a tiny bathroom, using a bookshelf to barricade the door. She told her children to be "absolutely quiet." "I said, 'There are bad guys out there now. We need to wait for the good guys,'" Roig said in an interview with ABC News. "If they started crying, I would take their faces and say, 'It's going to be OK. Show me your smile.'"
Just 29 years old herself, Roig drew on her training but, more so, basic humanity to give the children what she thought they needed to make it through.
"I'm thinking that I have to almost be their parent," she said. So she did what any parent would do. She told them how much she loved them. And she promised that everything would be OK.
"I wanted that to be one of the last things they heard," Roig said, "not the gunfire in the hallway."
Brock said that doing drills with younger children, a common thing post-Columbine, has produced two important conclusions.
First, kids faced with the mock version of a stressful event respond appropriately. And second, developing that appropriate response can make them feel they have the power to keep themselves safe -- and thus make the situation appear less threatening.
"I was kind of worried for a while there that by doing these new things called lockdown drills, we might be unnecessarily frightening kids and preparing them for an event that has a real low probability of occurring," Brock said. "Was the cost worth the benefit, especially since it's going to be so rare that we're going to have to employ these drills?"
"The answer," he said, "appears to be yes."