President Donald Trump supporters shake their fists at the media as Trump formally announced his 2020 re-election bid Tuesday, June 18, 2019, in Orlando, Florida. AP Photo/John Raoux

EL PASO, Texas — President Donald Trump has often railed about an “invasion of illegals” at the southern border, words echoed in a screed the El Paso shooting suspect apparently posted that called the attack that killed 22 people at a Walmart his response to an “Hispanic invasion of Texas.”

Some extremism experts believe that may not be an accident. They say historical data suggests a link between heated rhetoric from top political leaders and ensuing reports of hate crimes, only adding to the fears of those who could be targeted.

“We can’t say that Trump is at fault because these mass killings have existed for a long time,” said Carlos Tarin, a Mexican immigrant who has lived in El Paso for three decades, but the recent rancor over immigration “has woken up that feeling that had been sleeping.”

The rampage in Texas has brought new attention to the dangers of immigration-motivated hate crimes and violence in a country with 58 million Latinos amid daily political rhetoric from the White House, conservative politicians and the dark corners of the internet about migrants coming across the border.

Overall, statistics released by the FBI late last year showed hate crimes in the United States rose 17% in 2017 compared to the previous year, the third straight annual increase. There were 7,175 hate crime incidents in 2017, and of the crimes motivated by hatred over race or ethnicity, nearly half involved African-Americans and 11% were anti-Hispanic.

But an analysis of such FBI data over the years by the Center for the Study of Hate and Extremism at California State University-San Bernardino yielded more specific results when it came to intense political debates.

It found that during August 2017, the month of the violent clash between white-supremacists and counter protesters in Charlottesville, Virginia — when Trump infamously said there were “very fine people on both sides” — reported hate crimes nationally increased to 663 incidents, the second-highest tally in nearly a decade.

That was surpassed only by the month of November 2016 surrounding the rancorous presidential race won by Trump over Democrat Hillary Clinton, when reported hate crimes nationally soared to 758 incidents.

And after a terrorist shooting by a Muslim couple that killed 14 people in San Bernardino, California, in 2015, Trump made a campaign trail plea for a “total and complete shutdown of Muslims entering the United States” until lawmakers “can figure out what the hell is going on.” Over the next 10 days, reported hate crimes against Muslims and Arabs nationwide spiked 23%.

“We see a correlation around the time of statements of political leaders and fluctuations in hate crimes,” said the center’s director, Brian Levin. “Could there be other intervening causes? Yes. But it’s certainly a significant correlation that can’t be ignored.”

To be sure, linking political speech, however fiery, to acts of violence can be problematic. For one, people commit hateful and violent acts for all manner of reasons that have nothing to do with the public discourse. And federal hate crime data has long been criticized as incomplete, since not all areas report their incidents to the FBI and many cases go unreported to police. Researchers acknowledge those factors but say the numbers are striking nonetheless.

A team from the University of North Texas recently produced a study that found counties that hosted a 2016 Trump campaign rally saw a 226% increase in reported hate incidents over comparable counties that did not host such a rally.

“I’m convinced now that political rhetoric of elites influences the behavior of supporters,” said North Texas political science professor Valerie Martinez-Ebers. “This research confirms, at least in my mind, that the political rhetoric that’s happening today is influencing the American public’s actions.”

Martinez-Ebers noted there has been valid criticism that researchers haven’t looked for spikes in hate incidents after rallies by other presidential candidates. “We still need to do that,” she said.

On Tuesday, Trump defended his rhetoric on such issues as immigration and denied stoking divisions that spawned the violence, contending that he “brings people together. Our country is doing incredibly well.”

Trump earlier in the week called the weekend’s shootings in El Paso and Dayton, Ohio, barbaric crimes “against all humanity” and called for unity to respond to the bloodshed. But critics question whether he has the moral authority to lead that push given his past statements.

On Facebook alone, Trump’s campaign has run around 2,200 ads since May 2018 that mention the word “invasion” when referring to immigrants at the southern border, according to the social network’s political advertising archive.

Last month at a rally in Greenville, North Carolina, Trump questioned the patriotism of Somali-born Rep. Ilhan Omar of Minnesota and then stood silent for 13 seconds while the crowd loudly chanted, “Send her back!”

At a rally earlier this year in Panama City Beach, Florida, Trump noted the obstacles U.S. Border Patrol agents face in preventing migrants from coming into the country. “How do you stop these people?” he asked.

“Shoot them!” someone in the crowd yelled. Trump grinned, shook his head and said, “Only in the Panhandle can you get away with that statement. Only in the Panhandle!”

Heidi Beirich, of the Southern Poverty Law Center, says Trump’s words have fueled anti-immigrant hatred and amplified conspiracy theories that non-white immigrants are systematically replacing whites.

“What Trump has done has heightened those fears,” she said.

Without naming Trump specifically, former President Barack Obama tweeted this week: “We should soundly reject language coming out of the mouths of any of our leaders that feeds a climate of fear and hatred or normalizes racist sentiments.”

But the historical data also has hopeful examples, says hate crime researcher Levin. He noted that the “worst month for all hate crime” occurred around the Sept. 11, 2001, terrorist attacks. Six days later, President George W. Bush delivered an address to the nation denouncing anti-Muslim harassment and saying, “The face of terror is not the true faith of Islam.”

Anti-Muslim hate crime reports dropped by two-thirds the next day and for the calendar year 2002 as well.

For now, though, immigrants don’t have to look far to see incidents of discrimination.

Over the past year and a half alone, a man wearing a “Make America Great Again” hat pushed a Mexican immigrant onto the New York City subway tracks while shouting anti-Hispanic slurs.

The Hispanic mayor of a Seattle suburb was assaulted from behind at a block party by a man who disparaged his ancestry and policies supporting Latino immigrants. And a New York attorney was caught on video yelling at customers and employees at a Manhattan restaurant, saying he supposed they were in the U.S. illegally and his next call would be to immigration authorities “to have each one of them kicked out of my country.”

Antonio Velasquez, an evangelical pastor from Guatemala who has been in Phoenix for three decades, said many immigrants in his largely Hispanic neighborhood have grown increasingly scared in the last few years amid stepped up immigration  enforcement and growing racism.

“People really don’t go out anymore,” he said. “They’ll go to school and to church and to the park, but they really don’t like to leave the Hispanic neighborhoods.”

Kunzelman reported from College Park, Maryland. Associated Press writer Anita Snow in Phoenix contributed to this report.