One day after a mass shooting in El Paso, Texas, left 20 people dead and more than two dozen wounded, federal authorities announced that they were treating the incident as an act of domestic terrorism. Authorities confirmed that the shooter posted an anti-immigrant manifesto to the online forum 8chan only minutes before the attack, mimicking Donald Trump's rhetoric about immigrants, particularly those from Central and South American countries, representing an "invasion." He reportedly traveled nearly 10 hours from his town of Allen, outside of Dallas, specifically to target Hispanics in the border city.

Donald Trump has spent the entirety of his short political career singling out immigrants as one of the biggest threats to the country, endearing him to white supremacists like the self-described white nationalist Richard Spencer and former KKK Grand Wizard David Duke, who celebrated his election. The man who murdered 49 people at two mosques in New Zealand, and who reportedly inspired the shooter in El Paso, called Trump a "renewed symbol of white identity.". And the president famously said there were "very fine people on both sides" following the 2017 white supremacist Unite the Right rally in Charlottesville, Virginia. Trump's willingness to ignore, and at times encourage, the threat of white nationalist violence is providing a politically challenging environment for law enforcement agencies, according to The Washington Post. Speaking to the Post, Dave Gomez, a former FBI supervisor specializing in terrorism cases, said he believes FBI officials are wary of wading into what looks like a political fight:

"I believe [FBI Director] Christopher A. Wray is an honorable man, but I think in many ways the FBI is hamstrung in trying to investigate the white supremacist movement like the old FBI would," Gomez said. "There’s some reluctance among agents to bring forth an investigation that targets what the president perceives as his base. It’s a no-win situation for the FBI agent or supervisor."

While another anonymous Justice Department official disputed Gomez's claim, the Post notes that investigating right-wing violence has long been politically challenging. In 2009, then Homeland Security analyst Daryl Johnson wrote a report titled, "Rightwing Extremism: Current Economic and Political Climate Fueling Resurgence in Radicalization and Recruitment." Despite the fact that Johnson identified as a conservative himself and began the report during the Bush administration, right-leaning politicians and commentators called it a "hit job on conservatives". DHS responded to the political pressure by cutting Johnson's staff, and he left the department not long after. When he spoke to WIRED in 2012, after a white supremacist murdered six people at a Sikh temple in Wisconsin, there was reportedly a single analyst in the entire DHS who was dedicated to non-Islamic terrorism.

Trump's rhetoric seems to have repercussions beyond words, too. Researchers at the University of North Texas found that in counties where Trump held one of his 276 campaign rallies in 2016, the number of reported hate crimes spiked by 226 percent in the following months. Since the election, Trump has continued to escalate his rhetoric toward immigrants. At a rally in Panama City Beach, Florida, this past May, Trump again called Central American migrants applying for asylum an "invasion" and asked the crowd, "How do you stop these people?" When someone yelled back, "Shoot them," the president laughed and cracked a joke, saying, "That’s only in the Panhandle you can get away with that statement. Only in the Panhandle!" In July, after he repeatedly said four minority congresswomen should leave the U.S., a Fox News reporter asked if he was worried that "many people saw that tweet as racist and that white nationalist groups are finding common cause with you on that point?"

Trump responded, "It doesn’t concern me because many people agree with me."

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