At a press conference on August 15, President Donald Trump stood in the gold-encrusted lobby of Manhattan’s Trump Tower and refused to put the sole blame on white supremacists for the violence in Charlottesville, Virginia, last weekend (which included the death of 32-year-old Heather Heyer, as well as others injured, after a driver plowed into a crowd). Speaking to several reporters, the president argued that the so-called “alt-left” — a term created to create a false equivalence between those on the “alt-right” (which is essentially a rebranding of white supremacy) and from activists opposing fascism — brought comparable levels of hate and violence to recent Unite the Right rally.

“What about the alt-left that came charging at, as you say, at the alt-right?” Trump asked. “Do they have any semblance of guilt? What about the fact that they came charging with clubs in their hands, swinging clubs? Do they have any problem? I think they do.”

The president went on to rationalize the rally, claiming that some of the white nationalists, supremacists, and neo-Nazis present were “very fine people” who just wanted to stop Confederate statues from being torn down.

Trump’s comments exposed his sympathies. White supremacists have been integral to his political rise from the beginning, and his reticence to condemn them by name this past week has been telling. At a time when white extremists are the deadliest domestic terror group in the United States, Trump’s defense of the march — essentially walking back on earlier comments he’d made condemning white supremacists specifically — excuses their brutality.

It also puts the national security of the United States in jeopardy, experts say.

“It is clear that white supremacists feel that they are ascendant because the president isn’t pushing back hard enough,” Shahed Amanullah, former senior adviser in the Obama administration specializing on counterterrorism strategies overseas, said in an email to Teen Vogue. “You have well-armed, violent ideologues who have proven they are willing to instigate and participate in violence against civilians and institutions, and who feel they have a green light to continue their activities [because of the president].

“That is the definition of a national security threat,” Amanullah added.

For the last 16 years, white supremacist terrorists have carried out more violent attacks on U.S. soil than any other domestic group, according to data from the U.S. Government Accountability Office. The Center for Investigative Reporting and the Investigative Fund report that twice as many terrorist attacks were committed by right-wing extremists, including white supremacists, than terrorists who happen to identify as Muslim from January 2008 to the end of 2016. Right-wing extremists have also been the deadliest, with one-third of attacks they committed resulting in fatalities, compared to 13% of those by Muslim terrorists.

“The [Trump] administration and its policies are doing a lot to stoke white nationalism in this country,” J.M. Berger, an associate fellow with the International Center for Counter-Terrorism at the Hague, said in an email with Teen Vogue. “White nationalists have a larger base of support than a group like ISIS to begin with, and Internet providers are not nearly as aggressive at suppressing them.”

Since Trump rose to political power, white supremacists have continued to gain traction — and their attacks have grown more frequent. The George Washington University’s Program on Extremism released a report in September showing that white nationalist Twitter accounts grew by 600% in follower growth within four years and are growing exponentially more than foreign extremist groups like ISIS. In February, the Southern Poverty Law Center reported that the number of American hate groups more than tripled in 2016, to a total of 917. According to the Combatting Terrorism Center at West Point, 300 violent attacks on U.S. soil per year on average are committed by right-wing terrorists. And then, according to the Southern Poverty Law Center, there were nearly 900 acts of bias-related harassment and attacks the month following Trump’s presidential win; more than 300 of those attacks were toward immigrants or Muslims.