President Trump on Monday said it was imperative to combat mental illness and address immigration laws in the wake of mass shootings in El Paso and Dayton, Ohio, that killed 29 people and wounded dozens more.

What the president didn’t emphasize, however, was reforming America’s gun laws.

The popular demand for tougher gun controls — followed by the realization that not much is likely to change — has become a familiar and tragic pattern that has followed almost every mass shooting in the United States in recent years. But other nations have shown that it doesn’t have to be that way.

When New Zealand Prime Minister Jacinda Ardern announced in March that the country’s gun laws would change, it was less than 24 hours after a right-wing terrorist attack that killed 51 Muslim worshipers in Christchurch. Parliament subsequently banned military-style semiautomatic weapons, assault rifles and certain sizes of magazines and ammunition in April, and a buyback program was set up.

To U.S. observers, in particular, the almost immediate response might have appeared surprising for a country that long shared more similarities in its approach to guns with the United States than with the rest of the Western world. So, why can’t the United States get done what took only days in New Zealand?

How similar were gun laws in New Zealand and the United States before Christchurch?

On the surface, New Zealand and the United States appeared to have a relatively similar approach to guns until the Christchurch attack in mid-March. Both were among the only nations without universal gun registration rules, and both had strong gun lobbies that had stalled previous attempts to rein in gun owners’ liberties.

“In New Zealand, the gun lobby dictates policy to the government,” Philip Alpers, founding director of gun legislation research tool GunPolicy.org, told Australia’s ABC in the immediate aftermath of the New Zealand shooting. “They are listened to far too acutely by the government, and they have managed to water down every single attempt at improving the gun laws. The gun lobby is directly responsible for having defeated the amendments that could have prevented this crime.”

Sound familiar? New Zealand’s gun lobby shared many of its goals with America’s National Rifle Association, the world’s biggest gun lobbying organization, which supports aligned politicians financially and uses social media to attack its opponents. Some of the NRA’s arguments may have found a receptive audience in New Zealand. There were an estimated 250,000 gun owners there before the Christchurch attack, in a country of 5 million people.

Experts say that high rates of gun ownership in the United States have allowed a perception to emerge that mass gun violence is an anomaly.

Given that “there are so many law-abiding gun owners who do not commit violence,” said Daniel Webster, director of the Johns Hopkins Center for Gun Policy and Research, “the conclusion that many people draw is that mass shootings are due to evil or deeply disturbed individuals and not due to the wide availability of guns.”

That argument would work even better in New Zealand, where mass shootings and homicides are far more rare than they are in the United States.

So how did New Zealand manage to ban some weapons so quickly?

Unlike the NRA, New Zealand’s interest groups have predominantly lobbied the government quietly, rather than threatening politicians with the scorn of their powerful voter base. The perceived silence of those lobbying organizations led to some calls from gun enthusiasts for a bolder and more vocal stance. New Zealand’s gun lobbies were probably well aware, however, that they are not the NRA and never will be, despite the aspirations of some of their members.

The country’s lobby mainly represents a core of rural supporters, whereas more than 86 percent of New Zealanders now live in urban areas and form a largely liberal majority. In the United States, the ratio of citizens living in urban areas is slightly lower. More important, however, the U.S. system of representation and the way congressional districts are drawn increase the significance of rural voters disproportionately. That helps explain why the NRA can pressure politicians into following its agenda, even though NRA supporters account for only a small fraction of all U.S. voters.

“Our form of government, with a Senate that gives extraordinary power to rural states over urban states and is deferential to states’ rights, makes it difficult to advance relatively modest gun-control measures, much less more sweeping measures,” said Webster, the gun policy expert.

In contrast, New Zealand’s election system is designed in a way that the number of lawmakers a party has in Parliament is aligned with its share among all votes cast. The mixed-member proportional voting system — which is also in place in countries such as Germany — is supposed to prevent small interest groups from being able to gain disproportionate influence over lawmakers. To pass legislation, only a simple majority is needed.

Ardern was also less likely to face challenges from the courts that politicians would in the United States, where the Supreme Court has interpreted the Second Amendment as giving people the right to own guns. Those legal hurdles have been exacerbated by a gun lobby that has conveyed a perception that tighter laws are by definition a violation of the Second Amendment.

“The gun lobby has been very influential in convincing people the [Second Amendment prohibits any] form of gun control, which affects the politics over even modest measures,” Webster said.

As a result, the United States is likely to remain an outlier on gun reform.

For those who successfully changed the laws in the wake of deadly shootings, the U.S. stance is mystifying. Speaking to CNN’s Christiane Amanpour in May, Ardern said: “Australia experienced a massacre and changed their laws. New Zealand had its experience and changed its laws. To be honest with you, I do not understand the United States.”

Mahtani reported from Wellington, New Zealand.

This post was first published March 18. It was updated Aug. 5.

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