In the United States, one in four teenage girls have cut or burned or otherwise harmed themselves deliberately, according to findings from sociologists reported recently in The New York Times.

This statistic cannot be stage-managed. It is a stark, unignorable indictment of this country and the way that we are raising our children. It is not a state of affairs that can be explained away. A quarter of American girls, with no intention of committing suicide, mutilate themselves.

We must ask ourselves how things came to be this way and what we can do to make ours a world in which young people are not miserable.

It is important to begin by observing that although the number of boys engaging in this behavior is also alarmingly high — the national average for boys and girls combined is around 18 percent — in all but two states the percentage of girls who have injured themselves is double that of boys. The sexual disparity is unmistakable.

The problem is hardly a new one. For years researchers observed that the rate of self-harm among girls between the ages of 10 and 14 was increasing rapidly. Last fall the Centers for Disease Control, drawing upon emergency room admissions data, reported that it had tripled since 2009.

It seems facile to suggest that there is any single overarching explanation for this phenomenon. But Jean M Twenge, a professor of psychology at San Diego State University, has argued that economic uncertainty and other economic factors, the demands of education, and the use alcohol and drugs do not account for the meteoric increase. The answer she proposes is the use of smartphones and social media.

Few periods in American history have been as revolutionary as the last decade or so. Between 2009 and the present the use of smartphones has become ubiquitous among children. It is not uncommon for many young people to spend six or even nine hours a day in front of these screens, getting less sleep, spending less time engaged in other meaningful activities, engrossing themselves in a set of priorities and commitments that are utterly divorced from the real world in which they should be learning to live.

Nor, I think, is it especially helpful for children to communicate with one another at such extraordinary length in almost exclusively adult-free spaces. When I was an adolescent, getting in touch with a friend meant calling the other person's house, where it was likely that a parent or an older sibling would answer the phone. Sometimes you would have to exchange pleasantries about the weather with your best friend's mother before she would hand over the phone.

This was a better state of affairs, I think, for both children and parents: for the former because it helped them to learn what it was like to talk to adults other than one's own parents, and for the latter because it is good to have some idea of what your child is up to and when and with whom. Moreover, the time children spent engaged in impersonal communication was strictly delineated because other people had to use the same phone. This also applied to computers and dial-up internet in the days of those beige and black boxes, when AOL Instant Messenger was not an option at 1 a.m. because of the unholy screech made by the modem dialing in the living room.

Hell is not, strictly speaking, other people. But for a teenage girl, nine hours a day of other people evaluating your appearance and utterances as you attempt to negotiate their preferences and attitudes and jockey for some intangible sense of status is probably something very much like hell. Studies by Twenge and others have shown that depression is far more likely to be correlated with frequent social media use among girls than with boys, who in any case are more likely to use their devices to play video games. The first person I ever knew who "cut" was also the first acquaintance of mine to use a social media service of any kind (LiveJournal); she had gotten the idea from a YA novel called Cut, a lurid and almost romanticizing treatment of self-harm whose publication can only be defended as a kind of misguided attempts at raising awareness of a problem that has grown exponentially worse since it appeared in 2002.

Most adults do not have the luxury of deciding whether the way we live now is healthy. If you use a computer at work and your employer insists on being able to contact you at all hours, you have no choice but to keep your smartphone near you. This is not the case for children. There is no reason that a child at 10 — the average age at which an American now receives his or her own smartphone — needs to own one of these devices. The downside of waiting to give children these powerful tools designed for adults until they are emotionally mature enough to handle them is practically nil; the upside is, or should be, self-evident.