New Zealand Prime Minister Jacinda Ardern, right, speaks to reporters at the OECD headquarters in Paris, on Tuesday. (Thibault Camus/AP)

New Zealand Prime Minister Jacinda Ardern spoke out this week about a matter that has long puzzled many foreign observers of the United States: the country’s inability to rein in gun violence.

Speaking to CNN’s Christiane Amanpour, the prime minister 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.”

Ardern was referring both to a 1996 massacre in Australia’s Port Arthur, which killed 35 people and resulted in quick changes to gun laws by conservatives there, and similar action in New Zealand after a gunman killed 51 people in attacks on two mosques in Christchurch on March 15.

Within days, Ardern was able to temporarily impose tougher gun laws, backed by a broad cross-party consensus that action was needed. The changes were officially passed and made permanent by 119 members of Parliament in early April. Only one lawmaker opposed the reform.

New Zealand now bans military-style semiautomatic weapons, assault rifles and certain sizes of magazines and ammunition. A buyback program for gun owners will be in place until September. Exceptions were made for certain small-caliber semiautomatic rifles as a concession to New Zealand farmers, and regular hunting rifles were left untouched.

“I can recall very vividly the moment I knew that we would need to be here, doing what we are doing right now,” Ardern said when the laws were passed in early April, referring to the moment she was told about the shootings. “I could not fathom how weapons that could cause such destruction and large-scale death could have been obtained legally in this country.”

On the surface, New Zealand and the United States long appeared to have a relatively similar approach to guns before the Christchurch shootings. Both countries had what experts considered to be strong gun lobbies that had stalled previous attempts to rein in gun owners’ liberties.

Before the Christchurch shootings, changes to gun laws were proposed several times, but they were never treated with the same sense of urgency by lawmakers, amid protests from a small but, at that time, influential gun lobby.

“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 just after the Christchurch massacre.

But unlike the National Rifle Association in the United States, New Zealand’s lobby has largely tried to influence the government quietly, rather than threatening politicians with the scorn of its powerful voter base. The quieter approach reflected an awareness that the lobby represented only a small share of mostly rural supporters, whereas more than 86 percent of New Zealanders live in urban areas and form a largely liberal majority.

In contrast to the United States, where rural states hold extraordinary powers, 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. After the Christchurch shootings, this meant that changes could be passed quickly, as pro-gun interest groups realized that they were outnumbered and instead focused on negotiating exceptions for their other core supporters, including hunters.

Ardern was also less likely to face challenges from the courts than politicians would in the United States, where the Second Amendment has been interpreted by the Supreme Court as giving individuals the right to own guns.

While the New Zealand prime minister may have faced fewer challenges than would a U.S. president willing to restrict access to guns, her most recent remarks still hit a nerve. They came ahead of a Wednesday meeting in Paris, organized by Ardern and French President Emmanuel Macron, to discuss solutions for a separate issue: combating the spread of extremism online.

After the Christchurch attacks, Facebook said it deleted 1.5 million videos of the shootings within the first 24 hours.

Ardern, Macron and representatives from Britain, Canada and the United States will discuss Wednesday a voluntary pledge for more accountability on social media. Top corporate representatives are also expected to attend.

It is still unclear whether the United States will sign the document. In private negotiations, White House representatives have voiced concerns in recent days that some elements may clash with the U.S. Constitution’s First Amendment protection of freedom of expression. U.S. lawmakers have so far similarly remained hesitant to force social networks to take down content that may inspire acts of violence, citing similar concerns.

As in the case of gun control, Ardern has taken a different stance, arguing that preventing extremism and violence does not automatically limit freedom of speech.

Researchers agreed that U.S. caution may end up making the country an outlier, as more nations now rein in social media companies worldwide. It would not be the only issue on which the United States is increasingly isolated.

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