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Academics and national security officials agree far-right violence is the deadliest and most active form of homegrown extremism. There is disagreement on how to define the far right and what to call the many subcultures that fall into that category. NPR national security correspondent Hannah Allam looks at why the words matter when it comes to tackling the threat.
HANNAH ALLAM, BYLINE: At the University of Maryland's START center, there is a team of researchers tracking far-right extremism. Ask them what that includes and this is the response.
MICHAEL JENSEN: White supremacist, white nationalist, white extremist, sovereign citizen, antigovernment, patriots.
PATRICK JAMES: Neo-Nazis.
JENSEN: Neo-Nazis, skinhead. What else?
ELIZABETH YATES: I've seen anti-federalist recently.
ALLAM: That's Michael Jensen and Elizabeth Yates. Their colleague, Patrick James, adds a couple more.
JAMES: Anti-Muslim or anti-immigrant, like kind of xenophobic cases.
ALLAM: Keeping up with all the variations of far-right extremism isn't easy, but researchers say the more detail the better. Their work ends up in government briefings and congressional hearings, part of how policy is made to fight violent extremism. And the word choices are part of a bigger debate; actually make that two debates - one academic, one political. On the academic side, scholars are trying to come up with standard terms for the far right and its many subsets. Should they use white supremacist, white nationalist?
CYNTHIA MILLER-IDRISS: This is one of the most contested questions you're going to ask.
ALLAM: That's Cynthia Miller-Idriss, a professor at American University who's written extensively about the far right.
MILLER-IDRISS: I just came from meeting two weeks ago with a group of scholars across the country. And we spent the whole dinner practically talking about should we - can we come up with a term?
ALLAM: She and her colleagues didn't reach an agreement over dinner, but they believe it's a vital question. Words have power.
MILLER-IDRISS: Language matters because it's a reflection of how serious something gets taken.
ALLAM: Which brings us to the second debate, the political one. President Trump has dismissed white nationalists as, quote, "a small group of people." And he's retweeted white nationalist accounts. Following the White House lead, security officials avoid labels like white nationalist and white supremacist.
MARY MCCORD: I'm appalled that the leadership, at least some people, feel that they can't use those kind of terms.
ALLAM: Mary McCord is a former federal prosecutor who oversaw terrorism-related cases at the Justice Department. She says confronting a threat starts with calling it what it is. But rather than getting specific, some officials are adopting vague terms like ethnoviolence or racially motivated extremism.
MCCORD: These acts of violence we've seen recently - Tree of Life synagogue, the recent events in California, international events like in Christchurch in New Zealand - I mean, these are white supremacists.
ALLAM: Researchers point out that the administration's softer language doesn't apply when it comes to Islamist or far-left extremism. Art Jipson, a professor at the University of Dayton, has studied homegrown radicals for nearly 30 years, and he's seen just about every category out there - or so he thought. On a recent video conference with a State Department official, he heard some new ones.
ART JIPSON: And narco Marxist violent revolutionaries. And then they started using terms like Islamo terrorism and anarchic Islamic terrorist organizations and networks. I don't even know what that means.
ALLAM: So Jipson asked the State Department rep to explain.
JIPSON: The person made a joke about, oh, that's just the term my boss gave me to use in this webinar. And I'm like, what? You're using a term you don't even know what it means?
ALLAM: Jipson laughs when he tells this story, but in truth, he says, the wording issue is a serious one when it comes to tracking the nation's most dangerous fringe groups. Data collection, law enforcement training, public understanding - all of that suffers without a commonly accepted vocabulary.
JIPSON: Taking these threats seriously means defining the terms.
ALLAM: Debates over who gets to define a threat aren't new. And if history serves as an example, this one could last a while. After 9/11, a similar fight erupted over what to call Islamist extremists. That one has gone on for nearly two decades. Hannah Allam, NPR News, Washington. Transcript provided by NPR, Copyright NPR.