In the wake of the Parkland massacre, the age-old question, “Am I my brother’s keeper?” has a newfound relevance.

As another mass school shooting stuns Americans, it is time to talk about not just how to protect students from shooters, but also about what must happen so that fewer students become shooters in the first place.

It is crucial to talk about how more American children can grow up with the emotional, psychological, and spiritual security that comes from relationships where one is deeply cared for, connected, and known.

For what lies inside so many school shooters is a deep void of identity and relationship that they tragically seek to fill through nihilistic violence.

There is a sobering theme repeated over and over in the biographies of school shooters—the fatherlessness of a broken or never formed family.

Among the 25 most-cited school shooters since Columbine, 75 percent were reared in broken homes. Psychologist Dr. Peter Langman, a pre-eminent expert on school shooters, found that most came from incredibly broken homes of not just divorce and separation, but also infidelity, substance abuse, criminal behavior, domestic violence, and child abuse.

After the Sandy Hook Elementary School massacre, scholar Brad Wilcox called attention to the work of criminologists Michael Gottfredson and Travis Hirschi, which found the absence of fathers to be one of the “most powerful predictors of crimes .” He explained that fathers are role models for their sons who maintain authority and discipline, thereby helping them develop self-control and empathy toward others, key character traits lacking in violent youth.

The late rapper Tupac Shakur said, “I know for a fact that had I had a father, I’d have some discipline. I’d have more confidence. Your mother can’t calm you down the way a man can. You need a man to teach you how to be a man.” Shakur, who was murdered in 1996, started hanging out with gangs because he wanted to belong to a family.

In addition to structure and discipline, a boy’s relationship with his father can be a profound source of identity—or not. Dr. Warren Farrell, author of the “The Boy Crisis,” says that when a boy asks “Who am I?” the answer is that his identity is comprised of half his dad and half his mom. If he thinks his father has abandoned him, he fears he is not. Boys who do not have a strong relationship with their fathers may lack a model of healthy masculinity. Many of the school shooters struggled with a sense of “damaged masculinity” and sought to become “ultramasculine.” Langman says that at the end of this spectrum  is “getting a gun to suddenly have power.”

In fact, the fathers of three of the most infamous school shooters were absent from their sons’ lives. The father of Adam Lanza, the Sandy Hook shooter, had not seen his son in two years and later told reporters he wished his son had never been born. The adoptive father of Nikolas Cruz died when Cruz was 5 years old. And the father of 6-year-old Dedrick Owens, the country’s youngest school shooter, was in jail when his son killed his first grade classmate. Dedrick Owens’ father has said that he suspects his son’s crime was a reaction to his absence.

Since the 1965 Moynihan report, the breakdown of the American family has been hotly debated. Democratic Sen. Daniel Patrick Moynihan’s finding that fatherlessness would lead to poorer outcomes for African-American children was published at a time when only 25 percent of African-American households were led by a single parent. Today, 24 percent of white non-Hispanic families are headed by a single parent and the rate has reached 66 percent among African-Americans. If we don’t reverse current trends on marriage, the number of fatherless children will only grow.

Ultimately, if we make fatherlessness and family breakdown a partisan issue, we all lose. Both Presidents Barack Obama and George W. Bush promoted a National Fatherhood Initiative in their administrations. Because strong marriages promote strong bonds between fathers and their children, the Trump administration should emphasize both.

A good starting place would be to reduce the marriage penalties that have been built into our welfare system. A next step would be to elevate the contributions of ordinary men doing the extraordinary work of fathering. And if we directed 1 percent of the attention and media coverage we give to athletes, musicians, and movie stars toward fathers, perhaps more boys would grow up seeing them as role models. President Donald Trump, his Cabinet, Congress, and other leaders can also use their bully pulpits to lead in this direction.

#WhyWeDoThisWork Wednesday: When a Dallas middle school put a call out for mentors in the community to support 50 students without father figures present at a Breakfast with Dads, 600 men showed up. #OurSonsMatter pic.twitter.com/kRvtKRFReK

— The Broad Center (@BroadCenter) January 10, 2018

And the good news is that communities are devising creative ways to help make up for the absences of dads. One example is in Dallas, where Billy Earl Dade Middle School held its annual “Breakfast with Dads.” To ensure that all 150 male students who wanted a mentor would have one, an organizer put out a request on a Facebook page for 50 “volunteer fathers.” Nearly 600 men from all different walks of life and careers answered the call.

We cannot provide every fatherless boy with a dad, but we can start by respecting the unique role that fathers play in the lives of boys and encouraging more men to step into the lives of children who need a male role model.

To understand the brokenness of our children, Americans must take a deeper look at the brokenness of our families. We must do this together. We must be the keepers of all our country’s sons so that they can grow up to be one another’s. If we are going to prevent the next Parkland, we need to take seriously the need all our young boys and men have for a dad.