Donald Trump’s shooter used the most popular rifle in America. The AR-15 and Pennsylvania, explained

Thomas Matthew Crooks, who attempted to assassinate former Donald Trump on Saturday, used an AR-15-style gun to shoot Trump in the ear, kill former fire chief Corey Comperatore, and severely injure two other people at the rally in Butler, Pa.

Crooks shot from the roof of an agricultural tool manufacturing plant a few hundred feet from the rally with the semiautomatic rifle, which was legally purchased by his father. He was wearing a T-shirt promoting “The Demolition Ranch,” a YouTube channel for gun enthusiasts. It is not surprising that Crooks chose an AR-15-style gun, as the firearm has been used in numerous mass shootings in Pennsylvania and across the United States.

Sales of the firearm have gone up and down based on the political views of the president or expected president, and sales tend to peak after mass shootings that could spark gun control, according to Wall Street Journal reporter Cameron McWhirter, who cowrote a book on the history of the gun called American Gun: The True Story of the AR-15 with his colleague Zusha Elinson.

The AR-15 is the most popular rifle in America, according to the Wall Street Journal reporters. The gun has become a symbol of the gun rights debate in the United States, with Republican lawmakers wearing lapel pins in the shape of the gun and Jan. 6 rioters waving flags with the image that say “Come and take it.”

First designed in the 1950s, the AR-15 was initially intended to be a lightweight automatic rifle for the U.S. military. Its name stands for ArmaLite Rifle, the company that originally made the gun. It was the 15th weapon designed by the gun company.

The rights to the AR-15 were sold to Colt’s Patent Firearms Manufacturing Co. in 1959. Colt created a version of the gun for the U.S. military called the M16, and a semiautomatic version of the rifle for civilians called the AR-15 Sporter.

“Now you can buy a hot new combat rifle for sport,” Popular Science wrote about the AR-15 in early 1965, according to the Washington Post.

But the rifle wasn’t actually popular at first, McWhirter said in an interview. The number of AR-15s owned by civilians in the 1990s was estimated at 400,000. But by the 2020s, that estimate increased to 20 million, according to the WSJ reporter.

“They are everywhere,” he said.

Its rise in popularity can be attributed to political factors and marketing efforts, McWhirter said. The reputation of the gun’s military counterpart also improved over the years, he said.

Gun manufacturers also realized that the model is highly profitable, and versions of the weapon can now be found at gun stores with prices ranging from the low hundreds to several thousand, according to McWhirter.

Plus, the AR-15 is incredibly easy to use.

“It’s designed to not be difficult on your shoulder, and you can stay on target pretty quickly, and pretty easily,” McWhirter said. “That’s what it was designed to do and it does it pretty well.”

Colt’s patent expired in 1977, so other manufacturers began to make their own version of the rifle, which is broadly referred to as the AR-15, though some call them AR-style or AR-15 style rifles.

“Everyone fell in line and started to make their versions of AR-15s, and they all made a lot of money,” McWhirter said.

The ATF classifies the Colt AR-15 as a semiautomatic assault weapon, though gun advocates push back against the widely used term “assault weapon.”

According to the Trace, a nonprofit news website focused on gun violence, “military-style rifles” such as the AR-15 have been used in the deadliest shootings, but handguns are used in most shootings.

Although the military version of the gun has an automatic setting, soldiers typically use its semiautomatic setting so that they don’t waste bullets, leaving anybody in the United States with an AR-15 shooting at the same speed as those at war, McWhirter said.

While most people who own the gun aren’t out to hurt anybody, McWhirter said, the massive population of people who own the gun includes “disturbed people,” who “can use that gun to hurt people really quickly, as we’ve seen.”

“They feel like they can go to war with whomever they want to go to war with,” McWhirter said.

AR-15-style rifles have been used in high-profile shootings across the United States.

Nikolas Cruz used one to kill 17 students and staff members at Marjory Stoneman Douglas High School in Parkland, Fla., on Feb. 14, 2018. Payton Gendron, a white supremacist, used a modified AR-15 to kill 10 Black people at a supermarket in Buffalo on May 14, 2022. Salvador Ramos used an AR-15 to kill 19 children and two teachers at Robb Elementary School in Uvalde, Texas, on May 24, 2022. The weapon was also used in mass shootings at a movie theater in Aurora, Colo. on July 20, 2012 that killed 12 and injured 58, Sandy Hook Elementary School on Dec. 14, 2012, in Newtown, Conn., that killed 20 children and six employees, and a Las Vegas hotel on Oct. 1, 2017, that killed 60 people and wounded hundreds attending a music festival.

If Crooks wasn’t shot dead by the Secret Service, “he could have killed a lot of people really quickly,” McWhirter said.

The gun was a mass shooter’s choice in Pennsylvania even before it rose in popularity. In 1982, George Banks, a former Camp Hill prison guard, used both an AR-15 and an M-16 rifle when he killed 13 people, including his own children, in the 1982 Wilkes-Barre shooting in Luzerne County.

Fast forward to 2018, and two separate mass shooters used the rifle in the commonwealth.

In January 2018, Timothy Smith shot and killed four people at a car wash in Melroft in Fayette County with an AR-15 and a handgun.

Later that year, Robert Bowers shot and killed 11 congregants at the Tree of Life Synagogue in Pittsburgh on Oct. 27, 2018. He was armed with an AR-15 rifle and other weapons.

Just last year, Kimbrady Carriker went on a shooting spree last year in Kingsessing with a pistol and an AR-15-style rifle ghost gun, shooting and killing five people and injuring others.

Pennsylvania Democrats want to ban ownership of assault weapons like the AR-15.

Pennsylvania House Democrats advanced a package of gun control bills that included a ban on future sales of automatic and semiautomatic firearms in January. The package passed the House Judiciary Committee on party lines, and was referred back to the committee in March.

National efforts have also been unsuccessful.

A national assault weapon ban passed the U.S. House in 2022, but it died in the Senate. The House bill had support from all Pennsylvania Democrats in the chamber. Almost all Pennsylvania House Republicans voted against it with the exception of U.S. Rep. Brian Fitzpatrick (R., Pa), who represents of Bucks County and parts of Montgomery County.

A federal assault weapon ban that lasted from 1994 to 2004 was poorly worded, according to McWhirter, and so companies modified their guns to fit the law. AR-15 sales spiked before the ban, continued to increase during the ban, and spiked again after the ban, which was also influenced by changing views on guns and a post 9/11 sentiment, he said.

Democrats attempted to bring back the 1994 ban last December, but it was blocked by Senate Republicans.

The fight has remained partisan. Biden has advocated for a renewed federal assault weapon ban, and Trump’s campaign vowed to continue to protect gun rights, even after he had one pointed at his head.

States controlled by Democrats have enacted bans while Republican states have made it easier to buy weapons like the AR-15. All the while, battles play out in courts about these types of weapons, according to the WSJ.