A 20-year-old white man who drove eight and a half hours from his home in Maumee, Ohio, to attend a “Unite the Right” rally in Charlottesville, Va., Fields rammed his Dodge Challenger into a group of non-violent protesters who had gathered in the city to push back against the rally. He, as a result, killed Heather Heyer, a Charlottesville resident, and injured at least 19 others. Speaking to CNN, a high-school teacher of Fields said: “He really bought into this white supremacist thing. He was very big into Nazism. He really had a fondness for Adolf Hitler.”

What makes Fields’ car-ramming rampage a terrorist attack? If we take a glance at the definition of terrorism, the one used by the federal government, we’ll see the term defined as the “unlawful use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives”—and we’ll see, in turn, that Fields’ murderous action was exactly that.

Unlawful use of force? Yes. In furtherance of political or social objectives? Yes. While the second may be harder to prove in court, Fields’ attendance at a white-nationalist rally, his possession of a “shield” with the insignia of Vanguard America—a group that advocates for “a nation exclusively for the White American peoples,” though the group claims that it has no affiliation with Fields—as well as his former teacher’s comments all suggest that Fields is much more than a passive white nationalist.

But why does it matter that we call what Fields did an act of terrorism? Because not to do so wouldn’t only obscure the truth—it’d also be harmful to our national security, and how we defend against, prevent, and build national resilience to acts of domestic terrorism.

Since the Trump administration took office in January, there has been one case of lethal jihadist terrorism in the United States, and three cases of non-jihadist lethal terrorism.

On Jan. 31, Joshua Cummings, a convert to Islam and reportedly on a federal watch list, was arrested and charged with shooting and killing a security guard in Denver. Cummings later stated in an interview with The Associated Press that he pledged allegiance to ISIS.

In March, James Harris Jackson stabbed and killed Timothy Caughman, a 66-year-old African-American man, in New York City. NYPD Assistant Chief William Aubrey said at the time: “It is believed he was specifically intending to target male blacks. It’s been well over 10 years that he has been harboring his hate towards blacks.” In May, Jeremy Joseph Christian killed two men on a commuter train in Portland, Ore. The two men had stepped in to defend two Muslim women whom Christian was harassing. And in April, in Fresno, Calif., Kori Ali Muhammad, who had previously been deemed mentally incompetent to stand trial in connection to another murder charge, shot and killed three white men. According to Muhammad’s father, Muhammad believed that he was part of a war between whites and blacks and that “a battle was about to take place.”

As the first eight months of 2017 have shown, approaching the subject of domestic terrorism and homegrown extremism only as a matter of eradicating “radical Islamic extremism” would be to fundamentally misunderstand and oversimplify a problem that touches all corners of this country. Indeed, focusing on only one strand would be to ignore the similarities that exist among the many cases of domestic terrorism.

For example, just as Anwar al-Awlaki continues to inspire American jihadists, Jerry Drake Varnell, who was arrested in Oklahoma Saturday for attempting to detonate what he believed was a bomb, admired Oklahoma City bomber Timothy McVeigh for his anti-government fanaticism. For the sake of national security, both of these examples ought to be central planks of our broader conceptions of what counts as terrorism.

The death of Heather Heyer is a profound tragedy, and the loss of an innocent life is among the worst parts of what was a horrific weekend in Charlottesville. What is also troubling, however, after seeing images of those who participated in the rally, is the sheer number of young people in attendance. Probably for many Americans under the age of 30, our generational consciousness of terrorism began with the attacks on Sept. 11, 2001, when Osama bin Laden became the world’s most feared terrorist and al-Qaeda the world’s most feared terrorist group. While the threat from jihadist-related terror remains a very real one, with ISIS carrying the mantle of leadership, we risk overlooking deep domestic problems—like the one on Saturday—when we only, and incorrectly, see the terrorist threat as coming from abroad.

Surely we want to prevent today’s young people from ushering in the return of naked bigotry and hatred, and from actively participating as these forms of prejudice coalesce into lethal violence. To start, however, we must call what happened on Saturday what it is: terrorism.

Albert Ford is a program associate with the International Security and Fellows programs at New America, a nonpartisan think tank. The views expressed here are his alone.