Photo: John Locher/AP

On Saturday morning , a gunman at a Walmart in El Paso, Texas, shot and killed at least 20 people before surrendering to the police. By all accounts, Patrick Crusius, the 21-year-old alleged shooter, is a fan of President Donald Trump and his policies. According to the Southern Poverty Law Center, a “Twitter account bearing the suspect’s name contains liked tweets that include a ‘BuildTheWall’ hashtag, a photo using guns to spell out ‘Trump,’” and more. Incredibly, the nation woke up to more grim news on Sunday, with reports that a man suited up in body armor and bearing a rifle with high-capacity magazines had carried out a rampage in Dayton, Ohio, killing at least nine people and injuring 26. Little is known yet about the Dayton shooter, but a four-page manifesto authorities believe was written by Crusius and posted shortly before the El Paso attack is full of the kind of hateful rhetoric and ideas that have flourished under Trump. The manifesto declares the imminent attack “a response to the Hispanic invasion,” accuses Democrats of “pandering to the Hispanic voting bloc,” rails against “traitors,” and condemns “race mixing” and “interracial unions.” “Yet another reason to send them back,” it says.

Photo: Mario Tama/Getty Images

And now, this latest massacre in El Paso. Let’s be clear: In an age of rising domestic terrorism cases — the majority of which are motivated by “white supremacist violence,” according to FBI Director Christopher Wray — Trump is nothing less than a threat to our collective security. More and more commentators now refer, for example, to the phenomenon of “stochastic terrorism” — originally defined by an anonymous blogger back in 2011 as “the use of mass communications to incite random actors to carry out violent or terrorist acts that are statistically predictable but individually unpredictable.” Sounds pretty Trumpian, right? As I wrote in October: “The president may not be pulling the trigger or planting the bomb, but he is enabling much of the hatred behind those acts. He is giving aid and comfort to angry white men by offering them clear targets — and then failing to fully denounce their violence.” And as I pointed out on CNN earlier this year, there is a simple way for Trump to distance himself from all this: Give a speech denouncing white nationalism and the violence it has produced. Declare it a threat to national security. Loudly disown those who act in his name. Tone down the incendiary rhetoric on race, immigration, and Islam. Trump, however, has done the exact opposite. In March, in the wake of the Christchurch massacre, the president said he did not consider white nationalism to be a rising threat, dismissing it as a “small group of people.” A month earlier, in February, Trump was asked whether he would moderate his language after a white nationalist Coast Guard officer was arrested over a plot to assassinate leading journalists and Democrats. “I think my language is very nice,” he replied.