Last week, the National Rifle Association (NRA) publicly celebrated its success in striking down an assault weapons ban in Boulder, Colorado. Five days later, Boulder was the scene of a mass shooting, reportedly with the same kind of weapon that the city tried to ban.

On Monday, the nation’s attention was focused on the Rocky Mountain college town after a gunman reportedly killed at least ten people, including a police officer, at a local supermarket. CNN reported that one law enforcement official said the weapon used was an AR-15-style rifle.

That kind of weapon was at the center of a landmark legal battle between the gun lobby and the city of Boulder after municipal officials in 2018 “passed two ordinances banning the possession of assault weapons and large-capacity magazines in the wake of the mass shooting” at a school in Parkland, Florida, according to the Denver Post. Colorado has been the site of some of the most high-profile mass shootings in American history, including shootings at Columbine High School, Planned Parenthood of Colorado Springs, the Aurora Theater, and the STEM school in Highlands Ranch.

A federal lawsuit backed by the local chapter of the NRA aimed to invalidate Boulder’s local ordinance, and all other potential assault weapon bans in Colorado. At the time, right-wing activist John Caldara, who filed the lawsuit, insisted that “what Boulder is doing now is putting gun owners back into a closet. And that goes against everything Boulder claims to stand for.”

Last Thursday, a Colorado judge ruled that a 2003 state law — enacted by a Republican legislature and signed by Republican Gov. Bill Owens — preempts cities and towns from restricting assault weapons.

“Only Colorado state (or federal) law can prohibit the possession, sale, and transfer of assault weapons and large capacity magazines,” wrote Colorado state judge Andrew Hartman.

In 2019, Stanford University researchers published a New York Times op-ed detailing data showing that the federal assault weapons ban, in place from 1994 to 2004, correlated to a significantly lower rate of gun violence in the country. The research was buttressed by earlier academic studies suggesting that restrictions on assault weapons and high-capacity magazines can reduce gun casualties.

Since the federal assault weapons ban expired, states and localities have had to fend for themselves, while the NRA has fought to use state laws to block local communities from more stringently regulating firearms.

“Today, almost all states have a firearms preemption law that prohibits localities from regulating firearms in a manner more stringent than state law,” the NRA wrote in 2019. “These laws are vital as they prevent localities from enacting an incomprehensible patchwork of local ordinances. Without these measures unsuspecting gun owners would be forced to forego the exercise of their Second Amendment rights or risk running afoul of convoluted and potentially inaccessible local rules.”

In response to the Colorado ruling last week, the NRA published a triumphant article on its website, celebrating how the judge’s opinion could make it more difficult for other communities to try to regulate deadly assault weapons.

“The opinion is also very thoroughly and thoughtfully written, which will make it even harder to overturn, should the city appeal it,” the NRA wrote. “While the holding only applies to the Boulder ordinances, the principles behind the ruling will apply to other localities who are considering passing any similar counterproductive ordinances.”

The conservative outlet Free Beacon published a report declaring “Preemption winning streak continues for gun advocates.” The piece quoted Caldara insisting: “I was probably the most publicly known criminal in Boulder” for openly flouting the local AR-15 ban.

In a statement on the judge’s decision on behalf of the gun control group Colorado Ceasefire, Tom Mauser, the father of a Columbine shooting victim, said: “This is a bitter disappointment. Assault weapons have been the source of horrendous tragedies here in Colorado and across the nation. Clearly the people of Boulder do not want these weapons of war in their city.”

A year after the 1999 Columbine shooting, Colorado’s then-Republican legislature shielded gun manufacturers from lawsuits.

In 2013, the Democratic legislature and then-Democratic Gov. John Hickenlooper backed modest gun control reforms designed to better regulate firearms in the state. Pro-gun groups promptly mounted successful recall campaigns against Colorado lawmakers who backed the measures.

As news of Monday’s shooting in Boulder was being reported, the NRA tweeted out the text of the Second Amendment.

Meanwhile, witnesses described their fear and sadness about the normalization of gun violence.

“It seemed like all of us had imagined we’d be in a situation like this at some point in our lives,” one person who was inside the supermarket told the Denver Post.

Another witness told KDVR: “People my age, in my generation, are used to this.”