“It is reasonable to label this a political terror attack inspired by radical ideology, and while the killer is obviously primarily responsible, right-wing political leaders such as Trump carry some responsibility for creating the conditions that enable this kind of savagery,” Ernesto Verdeja, a Notre Dame professor who studies political violence, told Quartz.

Trump’s presidency has taken racist rhetoric from the fringes of the conservative movement and put it center-stage, particularly when it comes to immigration.

A “National Conservatism Conference” in July hosted by Tucker Carlson and other pro-Trump thinkers was intended to flesh out a unified theory of Trumpian conservatism. The speaker who received the most attention was University of Pennsylvania law professor Amy Wax, who explained that “embracing cultural distance, cultural distance nationalism means in effect taking the position that our country will be better off with more whites and fewer non-whites.”

The rhetoric used by Trump—from his calls to “send back” US lawmakers who criticized him to his references to “vermin” and “infestations”—mimics language that academics who study genocides like the 1994 slaughter in Rwanda say is dangerous because it de-humanizes political opponents. While this rhetoric isn’t new, it becomes more dangerous when in broadcast by authority figures.

“We are living in an era when some of our leaders have openly espoused white supremacy and conspiracy theories (like versions of the the Deep State, QAnon, Replacement Theory, and so forth), and have successfully pushed this dangerous rhetoric into mainstream political discourse,” Verdeja said. “This in turn feeds a growing network of extremist individuals and groups who have found a common cause, and see President Trump and others like him as ‘on their side,’ even if he has to appease the broader public on occasion with stilted and unpersuasive words of condolence.”

There are numerous examples of terrorists who have been inspired by Trump, including Cesar Sayoc, who said he mailed bombs to Trump’s enemies because he felt he had a personal connection to the president; James Fields, who told friends he admired Trump’s views on race and was sentenced to life in prison for murdering Heather Hayes with his car at a protest over Confederate statues; and a Canadian man who killed six people at a Quebec mosque.

“Such language isn’t new—it’s been at the root of most human tragedy throughout history, here in America and around the world,” former US president Barack Obama said in a statement after the shootings in El Paso and Dayton. “It is at the root of slavery and Jim Crow, the Holocaust, the genocide in Rwanda and the ethnic cleansing in the Balkans.”

Obama’s comparison to the US in the time of Jim Crow is apt: The Ku Klux Klan acted as political enforcers in the post-reconstruction South, terrorizing black communities to maintain the political power of the white establishment. Southern senators could condemn the tragedy of lynchings while ensuring that anti-lynching legislation never made it to a vote.

Trump condemned “white supremacy” in listless tones in a statement on Monday, mis-identifying the location of one of the weekend’s two mass shootings. But he did not call for any meaningful changes to US gun laws. Earlier, he did suggest that such legislation could be attached to a bill that would restrict immigration. In essence, the president said, we can’t change the gun laws until we give the shooters what they want.

The ties that bind law enforcement

The links between some Republican politicians and white nationalist groups, meanwhile, have made it harder for law enforcement to take action against them.

“There’s some reluctance among agents to bring forth an investigation that targets what the president perceives as his base,” David Gomez, a former FBI agent who oversaw terror investigations told the Washington Post. “It’s a no-win situation for the FBI agent or supervisor.”

Consider the tone set in 2009, when an analyst at the Department of Homeland Security was pushed out of his job for writing a memo warning about the dangers of right-wing extremist groups. Or, that the El Paso attack, the California synagogue shooting, and the massacre of 52 people at a mosque in New Zealand were all previewed on a public internet message board called 8chan.

Comparisons to how the US has battled Islamist terror groups are inevitable, and instructive. While undercover FBI agents spend enough time trying to track domestic terrorists in the Muslim community that they are regularly accused of entrapment, it seems comparatively little attention has been paid to white nationalists.

Part of the reason, according to experts who study the topic, is there is no analogue to federal laws that criminalize support for foreign terror groups. Law enforcement may be waking up. In May, the FBI distributed a memo warning of a threat from QAnon conspiracy theorists who believe that Trump is waging a secret war against international pedophiles. Today, the FBI Agents Association called for Congress to make domestic terrorism a federal crime.

The only country where this happens

In the ritual response to mass shootings, America’s moral compass is a satirical website, the Onion. After each report of innocents gunned down at worship or in class, it runs a story headlined “‘No Way To Prevent This,’ Says Only Nation Where This Regularly Happens.

Empirically, the US is an outlier on gun violence because it is an outlier on gun access. Americans have easier access not just to guns, but specifically to military-designed semi-automatic weapons with large magazines that are able to murder with efficiency.

As mass killings using these weapons have mounted, US lawmakers have considered attempts to ban “assault weapons,” to ban magazines of specific sizes, to institute background checks on purchasers or otherwise regulate their sale. None of them have become law. The most recent significant gun legislation, enacted by Republicans in 2017, ensured that people receiving disability benefits for mental impairment could still purchase weapons.

While the Trump administration has issued a regulation to ban “bump stocks,” a technology that effectively converts semi-automatic weapons into machine guns, the president said he would veto a bill to expand gun-buyer background checks that passed the House of Representatives. First, the bill would have to pass the Republican-controlled Senate, and that seems unlikely.

The near-total inaction of the US government in response to these attacks comes despite public opinion surveys that show support for expanded background checks and limits on military style weapons. Much attention is given to the difficult of legally describing what kind of weapons should be banned, but that hasn’t stopped other countries. A more salient explanation is the wealth of gun manufacturers and the power of the National Rifle Association in organizing a potent single-issue voting bloc against restrictions on guns.

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