By then, twenty of the children who had arrived at school that morning were dead, along with six grownups—that is a preliminary count—and the shooter, a twenty-year-old man named Adam Lanza, whose mother was among the adult victims. (Earlier reports had named his older brother, Ryan.) “The majority of those who died today were children, beautiful little kids between the ages of five and ten years old,” President Obama said in a press conference. And then he began to cry.

This is one of the worst school shootings in the history of a country that has had plenty of them. The images from Newtown are hard to shake: the children comforting each other, the parents for whom comfort now must feel useless; the seventeen-year-old who lived near enough to hear the shots and came running, looking for his nine-year-old sister. A teacher leading a line of students, many of them crying but each, with the orderliness of the very young, with hands on the shoulder of the child ahead. Other children had been told to find a buddy before making a break for it, and did. They were brave. The contrast here is not only between the civility of the children and the cruelty of the shooter, but between what was asked of them at this moment and how little the public and elected officials ask of themselves when it comes to doing something about gun violence. (One of the first questions was not just what kind of gun Lanza had but how many.) How do we find ourselves asking kindergarteners to be more courageous in the face of a gunman than politicians are in the face of the gun lobby?

Here is the difference guns make: A man comes to kill his mother. He shoots her and goes to the school where she works and, on his way down the hall, turns his weapon on some of her colleagues. He finds a room filled with kindergarteners; she is their teacher, they are all about five years old. He pulls the trigger and keeps shooting until the children are dead, too. Then he shoots himself.

In what sort of state of rage and nothingness do you have to be to take even one of those steps? Adam Lanza moved from one to another for reasons we will be sorting out for a long time, maybe forever. His mother is dead, and by the time the shooting stopped, so was he. The impulse and the guilt appear to be his alone. But a gun, with the momentum of shot after shot, the continuity of a round of bullets, gives such crimes more force. (As I noted in a post on the Jovan Belcher case, ninety-two per cent of domestic-violence murder-suicides involve guns.) Guns extend the reach of violence, and, with our national silence on senseless gun laws, so do we. Guns make it easier for a killer. They make it impossibly hard for parents who arrive, dazed and pleading, at the firehouse in Connecticut where the surviving schoolchildren were taken, and don’t find the one they were looking for there.

Photograph by Shannon Hicks/Newton Bee/AP.

See our full coverage of the Newtown shooting.

At that stage, the number of the victims and the name of the shooter hadn’t been established, but it was clear that something terrible had transpired. A few of the revellers near the bar were avidly watching the story develop. Others glanced at it occasionally, shaking their heads. Most people were ignoring the screen, talking to their friends, and drinking their beer—an attitude that wasn’t as heartless as it might seem. From three thousand five hundred miles away, the narrative emerging from Newtown seemed all too familiar. A lone nut arms himself like Rambo, drives to a locale packed with innocents, and savagely takes out his resentments on the world. In July, the location was a movie theatre in Aurora, Colorado. A few weeks later, it was a Sikh temple near Milwaukee. Now it was an elementary school in leafy Connecticut. Just another American horror movie.

For me, of course, it was something much closer to home. My holiday spirit having dissipated, I called my wife in Brooklyn and talked about what we should tell our two young daughters, both of whom attend local schools. Then I drove back to my mother’s house and turned on the BBC News channel, which was covering the shooting as if it had taken place in Glasgow or Grimsby. Other countries, the U.K. included, have experienced school massacres of this nature. In March, 1996, a former Scout troop leader called Thomas Hamilton entered a primary school in Dunblane, Scotland, and shot to death sixteen pupils before killing himself. But nowhere have mass shootings been as prevalent as the United States, and nowhere has the policy reaction been so pathetic.

As the coverage continued, the true scale of what had taken place—including the apparent execution of an entire kindergarten class—became clear. But did it really make much of a difference to the underlying narrative? At various points in recent years, the American gun plague has struck down college students, high-school students, department-store shoppers, moviegoers, and religious worshippers. Unstopped, it was sure at some point to claim the lives of kindergarten and grade-school students.

Deprived of much truly revealing footage from the scene, the BBC dug up some eyewitnesses, local residents, psychologists, criminologists, and an academic from Yeshiva University whom it billed as an expert on school massacres. (In what other country can you make a professional specialty of the mass shootings of children?) The presenters dutifully brought up many of the pertinent questions about gun control and school security, not that they, or anybody else here, was really expecting to get any persuasive answers. After watching so many of these terrible events from afar, a lot of Britons and other foreigners, including many who greatly admire the United States, have given up even trying to figure out why it doesn’t do more to prevent them.

In fact, things have gone in the other direction. The U.S.’s addiction to gun violence and its capacity to generate these acts of astonishing selfishness, cruelty, and nihilism is sometimes seen as an immutable national trait—something as American as baseball and fast food. From this perspective, producing crazed shooters like Adam Lanza is just one of those things that American does better than any other nation, the criminal equivalent of churning out New York comedians and Silicon Valley billionaires.

This thinking is wrong, of course. All societies have deeply troubled and alienated young men, some of whom end up violently lashing out at the world. But in most other advanced countries, such as the United Kingdom, which banned handguns after what happened at Dunblane, these misfits don’t have easy access to guns and the gun culture that glorifies them. During recent years, politicians of both parties, President Obama included, have been far too reticent about spelling out this elemental truth. In the immediate aftermath of the massacre at the cinema in Aurora, President Obama refused even to talk about the gun laws, preferring to keep the focus on the victims.

On Friday, it looked for a time as if the White House was going to give another pitiful response, especially when Obama’s press secretary Jay Carney, at his regular morning briefing, said that this wasn’t the day for a discussion of gun control. President Obama recognized the magnitude of the occasion and grasped that something more was needed. In his emotional statement, which the BBC ran live and then showed repeatedly, Obama artfully expressed the nation’s grief and horror and also called for “meaningful action to prevent more tragedies like this, regardless of the politics.”

They were only words, of course—words and tears. If we really want to persuade people overseas, people such as ones I grew up with, that what happened today was an aberration—a desecration of American values rather than a twisted display of them—more, much more, will be needed: a willingness to face down the N.R.A. and introduce proper gun control. Until such a display of national resolve materializes, the massacres will occur at intermittent intervals, the toll of needless deaths will climb, and our overseas friends will continue to shake their heads, saying, “It’s America, you know. That sort of thing happens there.”

Photograph by Jessica Hill/AP.

See our full coverage of the Newtown shooting.