At 2:21 pm on Valentine's Day, a Florida man named Nikolas Cruz walked into his former high school with a gas mask and an AR-15 rifle. A half-hour after the first gunshots, 15 people were dead. Two more would soon join them. The school's students clustered in the grass, cordoned from a wall of  cameras by a wall of police. The strangest thing about the event was how familiar it had become, in a country with a near-monopoly on school shootings and nearly twice as many guns per capita as any other country in the world.

Feminist and historian Roxanne Dunbar-Ortiz, 78, is best known for her 2014 book, An Indigenous People's History of the United States, and her 2009 memoir about growing up Okie. Her newest book, Loaded: A Disarming History of the Second Amendment (City Lights, 236 pages, $15.95), takes on the militaristic and white-supremacist origins of our country's unhinged love affair with guns.

Before her appearance at Powell's Books this Friday, we talked with her about mass murder, the cult of the Constitution and the takeover of the National Rifle Association.

WW: Does it seem to you that each mass shooting brings the same conversation, and the same results?
Roxanne Dunbar-Ortiz: People are just lost right now. When a shooting like this happens, when there are so many victims, when they're babies—you almost don't want to bring up the fact that we have to look deeper for the causes. You want an immediate solution. A mother yesterday asked Trump and Congress: "You have to stop this. Make it so children don't get guns." I was on the phone all day with reporters, and I hesitated: Is this the time to talk about history? But there's no better time for people to say, wait a minute, there must be some deeper cause.

What are people getting wrong about gun violence?
The left blames white nationalism. The right blames mental illness. Neither explains that it happens often here and nowhere else. But mass shootings account for a very small number of gun deaths: Many more women are killed in their home by guns. Men used to just knock women around, but rarely did death result. But with a gun on hand, there's a death. Half of the gun deaths are suicide. The proliferation of guns is a huge problem, but its cause is not lack of regulations. There were lots of regulations in the '70s when this started; going postal and school shootings started in the '70s.

But why not just pass gun regulations?
Seventy-five percent of the U.S., in every age group, some more than others, want to have gun regulations. But those same 70 percent, when asked about whether the Second Amendment means they have the right to bear arms, they support it. They always say, "I support the Second Amendment."

Until the '70s, the Second Amendment wasn't seen as very important—the gun lobby hadn't interpreted gun ownership as an individual right.
The NRA was previously more about recreation and target shooting. The [far right] took over the NRA in 1977, and in the 1980s, under Reagan, you had a flowering of these different sovereign citizens groups. In the '90s, you have the rise of the militias. These are white nationalist groups.

The reverence for the Second Amendment is not only a useful tool for gun nuts addicted to having guns. When you understand why it's in the Bill of Rights, you understand this constant regeneration of violence.

Why was it in the Bill of Rights?
The Second Amendment has to be understood for what it's for. There was no debate about the Second Amendment with militias. These things were already in the state constitutions and the Declaration of Independence. In the state constitutions, in particular in Virginia, where Thomas Jefferson insisted on this bill of rights which he had written into the state constitution, to provide for already existing citizens' militias.

Militias had existed since the 17th century. In 1642, in Massachusetts, 12 years after settlement by Puritans, they issued an order that every man—this meant white men—had to carry a weapon everywhere in public. Virginia did the same thing about 20 years later, even more extremely: You had to have a gun inside church, in the fields.

Were we worried about crime? Bears?
You have this parallel genealogy of the militias covered in the Second Amendment—to kill Indians to take their land, and slave patrols.

They were on land they'd forcibly taken from native inhabitants—burning down their villages, killing people, raping the women, killing everything that moved, destroying their food stores, burning their crops and then squatting on the land.

Carved out of these existing militias to kill Indians and keep them from coming back were the slave patrols, introduced in South Carolina. Slave owners there came from the very brutal slave society in Barbados.

What became of those militias after that?
This history isn't that different from New Zealand, Canada and Argentina. Later, Spaniards were copying the United States on the subject of ethnic cleansing. They did the same in Argentina.

During the armed occupation [of the South], immediately the slave patrols became illegal. But they reorganized themselves as the Ku Klux Klan when the Union pulled out. They formed rifle clubs. They didn't take the guns away from these white Southerners.

So if our history is similar, what made us so wild about guns?
The Second Amendment matters. Since it's a white right, a white supremacist right, it gets inscribed in the culture.

I don't think it's any accident, and I'm not the first person to point out that not all but practically 99 percent of mass shootings are carried out by white men. This goes back in part to the military. A good percentage of the white men who own guns—and 61 percent of gun owners are white men—a good percentage of them are combat vets. That's who's likely to have more than one gun: The average is eight. Not every man woman and child owns a gun. But they are hoarded.

So do we just have violence inscribed in our DNA?
With mass shootings, I think you have to look psychologically at how the civil rights movement affected white people, especially the Brown v. Board of Education ruling that desegregated schools in 1953. This was like an earthquake for white supremacy. I grew up in a rural farming community, I was 15 years old by then. I remember our neighbor bringing home an Ebony magazine and showing us what was going to happen.

This is the period when white nationalist organizations start popping up. The first was [the] John Birch [Society]—one of the Koch brothers was a charter member.

This rise of the Second Amendment is almost a time bomb that was planted in the Constitution. A mandate for the legality of settler violence and settler sovereignty. What's that right about? It's about taking all the property. They're a vestige, but they're very powerful. They have a voice in the presidency and in the Congress.

Roxanne Dunbar-Ortiz appears at Powell's City of Books, 1005 W Burnside St., 503-228-4651, powells.com, on Friday, Feb. 23. 7:30 pm. Free.