James and Jennifer Crumbley never anticipated that their then-15-year-old son, Ethan, would use the 9-millimeter Sig Sauer handgun Mr. Crumbley had bought — ostensibly as an early Christmas present — to kill four students at a Michigan high school. At least that’s the argument their lawyers made in court before Ms. Crumbley, last month, and Mr. Crumbley, almost two weeks ago, were convicted of involuntary manslaughter in separate trials. Prosecutors argued that the Crumbleys did not do enough to secure the gun and ignored warning signs that Ethan was planning to use it.

After every mass shooting by a teenager at a school, there is an instinct to look to the shooter’s parents to understand what went wrong. In the case of the Crumbleys, this seems obvious: Ethan left disturbing journal entries fantasizing about shooting up the school, and stating that he had asked his parents for help with his mental health issues but didn’t get it. His father said the family had a gun safe but the safe’s combination was the default factory setting, 0-0-0.

One factor that’s gotten less attention, however, is how the Crumbleys’ attitudes and actions reflect an increasingly insidious gun culture that treats guns as instruments of defiance and rebellion rather than as a means of last resort.

I’ve been thinking about this case a lot because I grew up in the 1980s and ’90s in a rural part of the Deep South where almost everyone I knew had guns in the house, unsecured, and mental illness was stigmatized and often went untreated. Church was considered a superior venue for counseling, and only “crazy” people sought professional help. If the evidence for criminal negligence is a failure to lock up a gun and ignoring signs of mental illness, many of the adults I grew up around would have been (and still would be) vulnerable to the same charges as the Crumbleys.

It’s convenient and comforting for many people to believe that if it had been their child, they’d have prevented this tragedy. But prison visiting rooms are full of good, diligent parents who never thought their kid would be capable of landing there.

My parents didn’t own a gun safe, but kept guns hidden away from us, which, like many gun owners at the time, they thought of as “secured.” The men in my family were all hunters and the guns they kept were hunting rifles, not AR-15s. (You can’t feed a family with deer meat that’s been blown to bits.) I knew my parents kept a handgun, too, but it was never shown to us, or treated as a shiny new toy.

Gun culture was different then. It would have never occurred to my parents to acquire an entire arsenal of guns and display them prominently around the house, as some people now do, or ludicrously suggest that Jesus Christ would have carried one. They did not, as more than a few Republican politicians have done, send out Christmas photos of their children posing with weapons designed explicitly to kill people at an age when those children likely still believed Santa existed. Open carry was legal, but if you were to walk into the local barbecue joint with a semiautomatic rifle on your back emblazoned with fake military insignia, people would think you were creepy and potentially dangerous, not an exemplar of masculinity and patriotism.

All of these things happen now with regularity, and they’re considered normal by gun owners who believe that any kind of control infringes on their Second Amendment rights. Children are introduced at a young age to guns like the Sig Sauer that Ethan Crumbley used. They’re taught to view guns as emblematic of freedom and the right to self-defense — two concepts that have been expanded to include whatever might justify unlimited accumulation of weapons.

“Freedom” is short for not being told what to do, even though the law very much dictates how and when guns should be used. “Self-defense” is often talked about as a justifiable precaution in the event of home invasion, though home invasions are as rare as four-leaf clovers and do not require an arsenal unless the invader is a small army. (It’s also worth noting that basic home security systems are far less expensive than many popular guns, which suggests that at the very least, some gun owners may be intentionally opting for the most violent potential scenario.) Most important, too many children are taught that guns confer power and can and should be used to intimidate other people. (Relatedly, any time I write about gun control, at least one gun owner emails to say he’d love to shoot me, which is not exactly evidence of responsible gun ownership.)

Mass shooters often begin with a grievance — toward certain populations, individuals they feel wronged by, society at large — and escalate their behavior from fantasizing about violence to planning actual attacks. A study from 2019 suggests that feeling inadequate may make gun owners more inclined toward violence. In the study, gun owners were given a task to perform and then told that they failed it. Later they were asked a number of questions, including whether they would be willing to kill someone who broke into their home, even if the intruder was leaving. “We found that the experience of failure increased participants’ view of guns as a means of empowerment,” wrote one researcher, “and enhanced their readiness to shoot and kill a home intruder.”

The study hypothesized that these gun owners “may be seeking a compensatory means to interact more effectively with their environment.”

Good parents model healthy interactions all the time. If their kids are struggling with a sense of inferiority or are having trouble dealing with failure, we teach them self-confidence and resilience. Parents who treat guns as a mechanism for feeling more significant and powerful are modeling an extremely dangerous way to interact with their environment.

What’s particularly hypocritical here is that the most strident defenders of this culture skew conservative and talk a lot about what isn’t appropriate for children and teenagers. What they think is inappropriate often includes educating kids about sex, about the fact that some people are gay or transsexual and about racism. It’s a perverse state of affairs: Exposing children to simple facts is dangerous, but exposing them to machines designed to kill is not. You can’t get your driver’s license until you’re a teenager, or buy cigarettes and alcohol until you’re 21, but much earlier than that, kids can, with adult supervision, legally learn how to end someone’s life.

Parents can’t ensure that their child won’t ever feel inferior or disempowered, or even in some cases become delusional or filled with rage. Teenagers do things that their parents would never anticipate every day, even if they’re close and communicative. Some develop serious drug habits or become radicalized into extremism or take their own lives.

One thing parents can ensure is that their children cannot get access to a gun in their house. The only foolproof way to do that is to ensure that there’s no gun in the house to begin with. Barring that, parents can make sure they are not reinforcing a toxic gun culture that says that displaying and threatening to use lethal machines is a reasonable way to deal with anger or adversity. That message makes the idea of killing someone seem almost ordinary.

That doesn’t prevent school shooters; it primes them.

Elizabeth Spiers, a contributing Opinion writer, is a journalist and digital media strategist.

Source photographs by CSA-Printstock and John Storey, via Getty Images.

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