This article was originally published after the Las Vegas shooting. It has been updated to reflect the shooting in Parkland, Fla.

"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." — The Second Amendment

The battle over guns has proven to be one of the most dangerous in America's culture wars — and with the murder of 17 people at a high school in Parkland, Fla., on Wednesday, the debate over how to regulate them continues.

The argument over gun control isn't merely about safety. It's about identity. The gun has transcended its function as a weapon to become a powerful cultural marker. It can signal what kind of person you are, and often to which tribe you belong.

"It's not about the guns. The guns are a symbol," said David Ropeik, author of How Risky Is It, Really? Why Our Fears Don’t Always Match the Facts.

Gun symbolism, social scientists say, was shaped by the nation's history. It has associations with the frontier and wars, with power and manhood. In modern political debates, it's associated with the idea of liberty from a "government [that] does too much to protect us and tramples on our personal rights," Ropeik said.

When a gun carries that kind of cultural significance, it's "a powerful image to fight against" if you're a gun control advocate, said John Donohue, a Stanford University law professor and gun policy expert, "and one that is largely immune from rational discussion."

The divide

Gun culture isn't just about "personal identity," said Adam Lankford, author of the 2015 study “Mass Shooters, Firearms, and Social Strains: A Global Analysis of an Exceptionally American Problem." The University of Alabama criminal justice professor said it's also about "shared identity — 'Do I fit in with my friends and family, according to the way we view the world and our values?'"

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"For one side, guns represent aggression, violence, and a somewhat paranoid and anachronistic perspective that you have to protect yourself from external threats," Lankford said. "For the other side, guns represent safety, security, and self-sufficiency — and wrapped up in some of that is often a form of traditional masculinity whereby the man of the house must be able to physically protect his family."

Justin Sollie, 27, is a libertarian-leaning Republican in Meridian, Miss. He grew up hunting, just like his father, and his grandfather before him. Sollie, a high school math teacher, owns guns for hunting and personal protection, but says he supports tighter restrictions on guns, including a ban on high capacity semi-automatic weapons. Sollie knows many people in his community would not.

"It's the idea of guns and gun culture that matters more than the gun itself," he said. To many Southerners, guns are "freedom."

People "cling" to their weapons because of "ingrained distrust of the government," Sollie said. Gun control advocates, he said, aren't fighting something tangible — they're fighting ideology.

The trouble with tribalism

The debate is notably partisan — or as Ropeik calls it, "tribal."

National polls show a clear split. According to a 2017 survey from the Pew Research Center, 91% of Republican and Republican-leaning gun owners say owning a gun is essential to their freedom vs. 43% of Democrats/Democrat-leaning gun owners. And even Republican non-owners are more likely than Democratic owners to view it as an essential right (61% vs.43%).

We are social animals and pressure to be loyal to party or tribe is strong, experts say.

"We aren't 325 million individuals who make up our individual opinions based on the facts," Lankford said.

The politics

Frustrated by lack of action after a student killed nine people at an Oregon college in 2015, President Obama said gun violence is “something we should politicize."

On the other side, gun rights groups gave $5.8 million to members of Congress in 2016, 98% of which went to Republicans, according to the Center for Responsive Politics. The non-partisan group that tracks campaign spending also reported that in just the 2016 presidential race, the National Rifle Association spent $10.6 million to support Donald Trump and $19.7 million to oppose Hillary Clinton.

The NRA puts out messaging about an intrusive government that wants to "take your guns," while its "pro-gun" lobbying opposes gun control measures. It has been successful.

The NRA has not responded to repeated requests for comment. However, it has historically accused opponents of exploiting mass shootings to push for restrictions they say demonize law-abiding gun owners.

Common ground

It seems as though the divide is impossibly stark, but experts say Americans share more in common than their Facebook feeds would suggest.

Large majorities in both parties support preventing the mentally ill and people on no-fly lists from buying guns, as well as background checks, according to a Pew Research Center survey conducted in March and April of 2017.

"Everyone for the most part is for safety and against senseless terror and death," said Jonathan Metzl, director of the Center for Medicine, Health, and Society at Vanderbilt University. "There's a sense of commonality. I think the problem is that it's very hard to find rhetoric that's not polarizing, considering that this debate is so beholden to so many different interests on all sides."

The desire for safety is basic and universal. The disagreement is over whether guns actually make one safer.

Three in ten American adults say they own a gun and 67% say protection is a major reason, Pew reports, despite a 2016 review in the journal Epidemiologic Reviews of 130 studies that found firearm restrictions are associated with fewer deaths.

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It's why gun sales spike after mass shootings, and why even people who know the data on gun safety find themselves internally debating whether they should own a gun.

After the Sandy Hook shooting, Lankford, the criminal justice professor whose 2015 study found the nation's gun ownership rate to be the strongest predictor of its number of public mass shooters, said he was asked if he would feel safer if professors on campus were armed.

"My answer was, 'I would feel safer if I had a gun, but I wouldn't feel safer if all professors were armed.' It really is a double standard. I trust myself, but I don't trust others," he said.

Lawrence Rutt, 48, an Army Special Forces veteran in Austin, Texas, didn't have a gun at home until this year, after he witnessed a drug bust while traveling for work. He said the incident rattled him, and he bought a 9mm handgun.

Rutt, a Democrat, says he supports stricter gun control measures and wonders aloud what it will take to change public policy.

"It's just a sad, sad moment when reporters ask the press secretary, 'when are we going to evaluate gun laws, and she said 'it's not the time.' Why is it not time to address gun laws right after a massacre in Las Vegas?" Rutt asked. "This was over 600 rounds. That is crazy. Holy mackerel, that's a lot of rounds."

Las Vegas gunman Stephen Paddock had an arsenal of 23 weapons in his hotel suite, including semiautomatic rifles. He possessed a little-known device called a “bump stock," which allows a semi-automatic rifle to mimic a fully automatic weapon by unleashing an entire large magazine in seconds.

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As the nation grapples with yet another macabre tragedy, many Americans are bewildered, fighting resignation in the face of a kind of violence that has begun to feel inevitable.

"The gun control argument is about fears," Ropeik said. "Some people are afraid of themselves or others being shot. Some people are afraid of losing control over their lives in a deeper, broader more comprehensive sense. That fear is deeper, and that fear is winning. Unless we validate that fear and respect it, it'll stay a battle with no solution."