The world has watched in horror as the Islamic State successfully recruited angry, frustrated and often mentally unstable young men to violence, channeling their disaffection and alienation into their warped ideology and eventually, deadly action.

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As a presidential candidate, Donald Trump seized on these events, making it a campaign theme of his to call out “radical Islamic terrorists” at home as well as overseas. In the second presidential debate, he lectured Hillary Clinton on her reluctance, and President Barack Obama’s to do the same.

“To solve a problem, you have to be able to state what the problem is or at least say the name," Trump claimed.

Open gallery view President Donald Trump walks from the Diplomatic Room of the White House, in Washington, Thursday, Feb 15, 2018, after speaking about the tragic school shooting in Parkland, Fla. (AP Photo/Carolyn Kas Credit: Carolyn Kaster/AP

Even back then, Trump was willfully ignoring a form of terrorism that was even more deadly than the Islamic threat, and getting deadlier. In 2015 a study found that since the September 11 attacks in 2001, twice as many people have been killed by white supremacists and right-wing extremists as have been killed by radical extremist Muslims pursuing jihad. And it has only gotten worse since then.

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According to the ADL, the number of white supremacist murders in the United States more than doubled in 2017 compared with the previous year, “far surpassing murders committed by domestic Islamic extremists and making 2017 the fifth deadliest year on record for extremist violence since 1970.” White supremacist and others on the far-right committed “59 percent of all extremist-related fatalities in the U.S. in 2017, up dramatically from 20 percent in 2016,” the organization reported.

Trump’s has consistently applied a double standard in his responses to shootings, bombings and other acts of violence. As soon as a perpetrator is identified in any way with the Arab or Muslim world, he has been quick to label the act as Islamic terrorism, usually using it as an opportunity to promote his anti-immigration political platform.

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But when a perpetrator of violence is linked to white supremacy or racist views, he has refused to call it out by name.

Open gallery view FILE - In this Saturday, Aug. 12, 2017, file photo, white nationalist demonstrators walk into the entrance of Lee Park surrounded by counter demonstrators in Charlottesville, Va. Unease over violent Credit: Steve Helber/AP

The Atlantic’s Ta-Nehisi Coates has written that “in Trump, white supremacists see one of their own.” Presumably reluctant to alienate this portion of his political base, Trump will point his finger at any other factors - usually mental instability, or the failure of those around the disturbed would-be assailant to recognize them as dangerous. The most famous example of this was when Trump stopped short of pinning the murder of 32-year-old civil rights activist in Charlottesville by a man who marched in the city’s white supremacist rally. Instead, Trump chose to generally condemn violence on "many sides” a reaction that earned him praise from former KKK Grand Wizard David Duke, who was also a vocal supporter of Trump during the presidential campaign.

And now, it has been revealed in the media - though not yet confirmed by authorities - that Nikolas Cruz, who slaughtered high school students and teachers with an AR-15 rifle, also had ties to white supremacists. According to the leader of a group called Republic of Florida, Cruz had participated in at least one “ROF Militia” training exercise.

That group’s website describes itself as “a white civil rights organization fighting for white Identitarian politics, and the ultimate creation of a white ethnostate [sic] so we can be free from anti-white policies and have policies that reflect our values as white westerners. The ROF Militia is the armed forces of the Republic Of Florida.”

Open gallery view Public defenders are seen on screen at the first appearance court for high school shooting suspect Nikolas Cruz(C) on February 15, 2018 at Broward County Court House in Fort Lauderdale, Fla. Credit: SUSAN STOCKER/AFP

If confirmed it would not be the first instance of individuals linked to a white nationalist groups being involved in mass shootings. Only two months ago, another school shooting was committed, this one by Bill Atchison at the at Aztec High School in New Mexico. Like the Florida shooter, he identified with white supremacy, frequenting hate sites and those affiliated with the so-called alt-right, where he glorified past school shooters.

White nationalist ideology, characterized by violent hatred of immigrants and ethnic minorities, is experiencing a troubling surge in the Trump-era, and heady with that success, is actively seeking to move into the mainstream of American culture.

With a body count in the U.S. far higher than any Islamic terror group has amassed, it is time for President Trump to take his own advice. Evidence is gathering that Cruz was not simply a mentally unstable loner, but one whose act of terror was inspired and assisted by militaristic white supremacy.

Trump can only begin to solve this deadly problem by - finally - calling it by its name. If he fails to do so, it will be an admission that he himself is a big part of the problem.

UPDATE: Doubt has now been cast on claims that Cruz had trained with the Republic of Florida militia. According to the ADL, "a member of an alt right discussion forum wrote that all of the claims were false and were part of an elaborate attempt to troll a network news reporter and other media outlets." The Tallahassee Democrat reports that "local law enforcement sources have not found a connection between accused Parkland school shooter Nikolas Cruz and a Tallahassee-based paramilitary group."