The horrific attack on two New Zealand mosques that killed at least 50 people was fueled by xenophobic, ethno-nationalistic and anti-immigrant feelings that seem to be rising worldwide – a tide of hatred that is taking many of its cues from the United States, some human rights leaders say.

The movement is being led by a small but vocal group of Americans who have sought to craft a narrative that white racial identity is in danger. In an interconnected, internet-enabled globe, their ideas migrate quickly from one continent to another.

“The United States is the epicenter of the world in terms of how white identity is seen,” said Karam Dana, a professor of Middle East politics and director of the American Muslim Research Institute at the University of Washington Bothell outside Seattle.

The New Zealand attack comes after recent racial violence in the U.S. Domestic extremists killed at least 50 people in the United States in 2018, which makes it the fourth-deadliest year for extremist-related killings since 1970, according to the Anti-Defamation League, a non-profit that fights anti-Semitism and all forms of bigotry. White supremacists committed the majority of the murders in 2018, the ADL said.

In 2017, clashes between counterprotesters and white nationalists in Charlottesville, Virginia, led to injuries and a death, making the college town synonymous with racial unrest and amplifying the message of white nationalists. More recently, a gunman opened fire in October inside a Pittsburgh synagogue, shouting hate for Jews and killing 11 people in the 20-minute attack. Authorities say the gunman had made anti-immigrant posts on social media.

“Modern white supremacy is an international threat that knows no borders, being exported and globalized like never before,” ADL CEO Jonathan Greenblatt said. “The hatred that led to violence in Pittsburgh and Charlottesville is finding new adherents around the world. Indeed, it appears that this attack was not just focused on New Zealand; it was intended to have a global impact.”

The brazen attack in the town of Christchurch began with social media announcements from the killer that he soon would be streaming his rampage. A 17-minute video stream of horror unfolded on Facebook, since taken down, in which dozens of worshipers at two mosques were massacred indiscriminately with high-powered weapons. Police finally arrested the suspect along with three other people.

A hate-filled manifesto believed to be written by the New Zealand attacker included references to the Second Amendment, with the gunman writing that he hoped conflicts over firearms would eventually lead to the United States splitting along political, cultural and racial lines. He also wrote that he supports President Donald Trump “as a symbol of renewed white identity.”

In a news conference Friday, Trump said he had not seen the manifesto and did not see rising white nationalism.

“I don't really. I think it’s a small group of people,” Trump said.

Domestic terrorism goes global

Anti-immigrant and ethno-nationalistic actions have been on a sharp rise in the West over the past four years, according to data collected by E. Tendayi Achiume, a U.N. special rapporteur on contemporary forms of racism, racial discrimination, xenophobia and related intolerance.

That increase began in 2015 with the arrival of a small number of refugees in Europe who were fleeing war in Syria and elsewhere, said Asli Bali, professor of law and faculty director of the Promise Institute for Human Rights at the University of California-Los Angeles.

It was further fanned by growing economic anxiety, rising inequality and narratives that tell whites those problems are driven by immigrants and people of color. Another often-cited statistic is that the United States will cease to be majority white within several decades. The nation is 76.6 percent white today, according to the U.S. Census Bureau.

These trends can be observed in most of the Western world: From Switzerland to Germany to New Zealand to the United States and some Scandinavian countries, resistance to the idea of changing demographics has been on the rise, Dana said.

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It's also spreading beyond white-majority nations. Globally, xenophobic and ethno-nationalistic violence and rhetoric has been rising for years but have largely been overlooked in the West, Bali said. For example, migrants from Mozambique, Mali and Zimbabwe coming into South Africa have been subject to attack. In 2017 and 2018, immigrant shops were burned and their owners beaten. A survey last year found that 30 percent of South Africans blame the violence on "foreigners stealing jobs from hard working South Africans."

Such attacks mirror much of the vitriol that’s coming out of many U.S.-based alt-right websites and other media sources, where racial epithets and statements disparaging Hispanics, women, Muslims, African-Americans and Jewish people run rampant. In one instance, William Daniel Johnson, chairman of the American Freedom Party, a white nationalist group based in New York, said: "Europe is becoming Muslim. Every people in the world can have their own country except white people. We should have white ethno-states."

The attack in New Zealand reflects a growing maturation of the white nationalist movement globally, which increasingly appears to be taking its inspiration from attackers in the U.S., says Eric Ward, executive director of the Western States Center in Portand, Oregon, which monitors hate crimes and provides tools to combat extremist views.

“Extremists in other parts of the world are now taking their cue from the increase in violence here,” Ward says.

Richard Cohen, president of the Southern Poverty Law Center, says the New Zealand attacker’s manifesto bears the “unmistakable fingerprints” of the alt-right.

“We – and that includes policymakers and the law enforcement community, in particular – must begin to view what we call ‘domestic terrorism’ through a global lens, just as we do the threat of groups like ISIS, because the growing white supremacist movement represents a clear and present threat to democracies across the world,” he says.

Made in the U.S.A.

New York University communications professor Helio Fred Garcia said the language used by candidate and now President Trump has had a direct effect on inspiring people to commit acts of violence. Trump has also called Mexicans rapists and suggested there were "people that were very fine people, on both sides," in Charlottesville, where white nationalists carried Nazi flags and chanted "Jews will not replace us."

“We are seeing a growing number of people who are never on any terrorist watchlist suddenly commit these acts, and they often directly use language that has been a staple of the president’s rhetoric, such as calling immigrants ‘invaders,’” Garcia says.

Garcia says Trump’s inflammatory language around migrant caravans heading to the southern U.S border, which he has often described as an invasion, is an example of what extremists respond to with action. In Pittsburgh, the man who killed 11 people at the Tree of Life synagogue posted on social media that Jews were bringing in an invasion of nonwhite immigrants and that he couldn't "sit by and watch my people get slaughtered."

“It’s time for political leaders to hold the president accountable,” Garcia says.

After the attack in New Zealand, the president shared his condolences on Twitter, calling it senseless.

"My warmest sympathy and best wishes goes out to the people of New Zealand after the horrible massacre in the Mosques. 49 innocent people have so senselessly died, with so many more seriously injured. The U.S. stands by New Zealand for anything we can do. God bless all!" Trump tweeted.