The attempt on former President Trump’s life at a campaign rally in Pennsylvania on Saturday felt familiar in a uniquely American way.

The shooter trained his AR-style rifle on people gathered far from his rooftop perch, echoing the mass shooting in 2017 in which a gunman opened fire on a music festival from the 32nd floor of a Las Vegas hotel.

Law enforcement said the shooter was 20 years old and got the gun he used from home — just like so many other young shooters who have left bloody trails through this nation’s schools and churches, bars and other community gathering places.

“Time and time again our communities are shaken by acts of gun violence that have invaded what should be our safe places,” said Angela Ferrell-Zabala, executive director of the gun control advocacy organization Moms Demand Action. “But they are a consequence of our country’s weak gun laws and guns everywhere culture — laws that allow hate to be armed with a gun to easily take someone else’s life.”

Amid denouncements of political violence from leaders and average Americans on both sides of the political aisle, the nation’s great gun divide felt newly raw Sunday — but hardly changed. Despite their presidential candidate nearly being shot dead, there were no outward calls from leading Republicans for the party to ease its ardent support of gun rights.

Still, the shooting provided a new and particularly powerful example of yet another American institution — this time the electoral process — falling victim to the vast proliferation of modern firearms. And that could matter as courts across the country and in California continue to weigh when, where and why such weapons may be restricted, if at all.

Right now, federal courts are considering challenges to a California law banning exactly the sort of AR-style rifle used by the alleged shooter, Thomas Matthew Crooks, 20, of Bethel Park, Pa.; another banning people Crooks’ age and younger from possessing firearms; and a third barring people from carrying firearms into an array of “sensitive” places — including public gatherings and special events.

A person is removed by state police from the stands after a gun was fired at Republican presidential candidate Donald Trump in Butler, Pa., on Saturday.

(Rebecca Droke/AFP via Getty Images)

Like the Vegas shooting, where a gunman killed almost 60 people and injured hundreds of others, the attack Saturday raised questions about how to define such sensitive places, and how to determine whether a certain type of firearm or accessory is so dangerous that it falls outside the protections of the 2nd Amendment, legal experts said.

Such questions hold added weight in the wake of the U.S. Supreme Court’s 2022 decision in New York State Rifle & Pistol Assn. vs. Bruen, where the high court said most gun laws are legitimate only if they are rooted in the nation’s history and tradition or are sufficiently analogous to some historic law.

In October, U.S. District Judge Roger Benitez, of San Diego, citing the high court’s Bruen decision, ruled that California’s ban on the sort of AR-style weapon used Saturday was unconstitutional because it was not rooted in history — and because assault-style rifles are sufficiently common and not uniquely dangerous.

“Like the Bowie Knife which was commonly carried by citizens and soldiers in the 1800s,” Benitez wrote at the start of his decision, “ ‘assault weapons’ are dangerous, but useful.”

Of course, assault rifles are far more dangerous than Bowie knives, with a vastly different range for inflicting harm. Federal authorities, for example, said Crooks shot Trump from an “elevated position outside of the rally venue” — which the Washington Post estimated was about 430 feet from where Trump was speaking.

Darrell A.H. Miller, a professor at University of Chicago Law School who studies 2nd Amendment law, said there is a “fairly well established” legal tradition declaring political rallies and other electoral events as sensitive places where guns can be prohibited.

However, Saturday’s shooting raised new questions about the scope of such restrictions and others like it — and about the nature of “sensitive places” and how their boundaries can and should be defined, he and other experts said.

“Sensitive places doctrine, to the extent that it is currently being developed, may need to be attentive to changes in firearm technology over the last 200 years,” Miller said in an interview Sunday.

Legal experts said the shooting could also help gun control advocates argue that such high-powered, long-range weapons are uniquely dangerous, even if they are commonly owned, and that bans on them in California and elsewhere are therefore in line with other longstanding bans on particularly dangerous weapons such as machine guns.

Steve Gordon, a retired LAPD special weapons team officer and sniper, said the shot that struck Trump was not particularly difficult with a little training, despite the distance.

“That type of rifle is standard issue to the police/military and that is not a difficult shot to make with that weapon system,” Gordon told The Times.

Congressional Republicans and the Biden administration have said Saturday’s shooting will be investigated thoroughly, including to determine if anything could have been done differently to prevent it. What may come of those probes is unclear.

Trump’s shooting also could be cited as another data point — a historically monumental one — in support of laws, such as California’s, that bar the sale of such weapons to those under 21, regardless of whether Crooks personally bought the weapon or not.

Gun control advocates could use the added evidence of the unique threat that high-powered, long-range weapons pose in the hands of unstable young men, particularly given the uphill battle they face in defending firearms restrictions post-Bruen.

The U.S. Supreme Court recently ruled that domestic abusers can be precluded from possessing firearms, but it has ruled against firearms regulations in other instances. Just last month, the high court struck down a federal ban on bump stocks — an accessory that allows gunmen to fire off rounds much more rapidly, and which were used in the Vegas shooting.

Courts aside, Trump’s shooting has already entered the national gun debate in a major way.

For example, when the National Rifle Assn. offered prayers to Trump, law enforcement and others at the rally in a post on the social media platform X, Shannon Watts — a co-founder of Moms Demand Action and the affiliated group Everytown — responded with a bristling retort suggesting hypocrisy on the NRA’s part.

“The NRA’s extremist agenda ensured a 20 year old would-be assassin had access to a weapon of war, rendering even the most highly trained security forces incapable of protecting anyone — from school children to former presidents,” Watts wrote.

She then noted that such weapons have been used in recent years to murder people at a grocery store in Buffalo, N.Y., a nightclub in Orlando, Fla., and schools across the country, from Santa Fe, N.M., to Uvalde, Texas, to Parkland, Fla.

Others made similar connections.

“If you keep talking about the assassination attempt don’t you dare tell the kids who survive school shootings and their families to ‘just get over it,’ ” wrote David Hogg, a survivor of the shooting that killed 17 and wounded others at his Parkland high school in 2018.

Hogg was apparently referring to comments Trump made about the need to “get over” a school shooting in Iowa earlier this year, which were roundly condemned by gun control advocates and survivors.

What happened Saturday was “unacceptable,” Hogg wrote, but so is “what happens every day to kids who aren’t the president and don’t survive.”

Times staff writer Richard Winton contributed to this report.