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The greatest terrorist threat is the one we rarely talk about

Two new studies suggest that non-Muslim terrorism is a greater threat to Americans than Muslim extremism.

The most lethal terrorists in the United States over the last decade have looked more like Charleston church shooter Dylann Storm Roof than Osama bin Laden.

Since the attacks on September 11, 2001, nearly twice as many Americans have been killed by non-Muslim extremists than by jihadists, according to a new count compiled by New America, a Washington-based research center. The study examined violence by white supremacists, anti-government fanatics and Christian fundamentalists in the past 14 years, finding that individuals identifying with those groups carried out 19 attacks, killing 48 Americans, while self-proclaimed jihadists carried out 7, killing 26.

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The count, which tracks all Americans "indicted or convicted" for "terrorism related crimes," was updated after Roof's indictment for killing  nine people at a historic black church in Charleston, South Carolina, last week.

The data suggests that attacks by white supremacists are becoming more common: Of the 48 who have died at the hands of right-wing radicals since 9/11, 45 have lost their lives since Barack Obama became president.

Mark Potok of the Southern Poverty Law Center said that isn’t a coincidence.

“The growth of these movements is more or less a direct result of the election of BarrackObama and what it represents,” Potok told msnbc. “And what it represents is the coming disappearance of a white majority in the United States. We are living through a serious backlash, and people will die as result.”

"The growth of these movements is more or less a direct result of the election of Barrack Obama and what it represents."'

A 2009 report from the Department of Homeland Security predicted that very backlash. The report warned that the combination of a weak economy and an African-American president could provoke a violent response from white reactionaries. But conservative media and elected officials denounced the analysis as a political attack, and the report was withdrawn. Two years later, The Washington Post reported that the analytical team behind the report had been “effectively eviscerated.”

Daryl Johnson, a former counter-terrorism analyst for the U.S. government and the main author of the 2009 report, told msnbc that the U.S. government currently employs hundreds of analysts focused on Islamic extremism, but only a couple dozen who monitor domestic terror.

Johnson believes that imbalance is dangerous, suggesting new African-American activist groups like the Black Lives Matter movement will provoke further backlash.

"Even as it resonates in minority communities, the movement could inspire more whites to move to the fringe and maybe those on the fringe will be pushed over the edge," said Johnson. "The Trayvon Martin case apparently resonated with Dylann Roof. I'm sure a lot of white males saw the way that case played out and took the side of the George Zimmermans of the world, or the white police officers of the world."

Johnson argues that the U.S. government could decrease the likelihood of violent backlash by stepping up monitoring of white nationalist websites, encouraging communities to report people who advocate for white supremacist violence, and funding counter-messaging efforts to combat the white nationalist narrative in susceptible communities.

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The nation's police departments appear to share Johnson's concerns about the threat of domestic terror. This week, national security expert David Schazner and sociologist Charles Kurzman published a survey of American law enforcement, which found that 74% of the nation's police and sheriffs' departments view anti-government violence as a threat to their jurisdictions, while only 39% said the same about “Al Qaeda-inspired” violence.

But to Brian Levin, director of the Center for the Study of Hate & Extremism at California State University, non-Muslim extremism isn’t a greater threat than Muslim extremism -- only a less visible one.

“The best use of these new reports is not to say that domestic terrorists are a bigger threat than foreign terrorists,” he said. “But rather to say that our resources are not being adequately deployed against the real and significant terrorist threat that comes from domestic extremists.”

However, Kurzman believes his research supports the idea that the government has overestimated the threat posed by Muslim extremism.

“We constructed our current homeland security institutions and policies based on the fears, after 9/11, that we might see many waves of attacks on a scale equivalent to that tragedy," Kurzman told msnbc. "Fortunately, we have not seen as many Muslim extremists in the United States as we were warned to brace ourselves for.”

"We have over 14,000 murders each year and violent extremism accounts for far less than one percent."'

Kurzman stresses that neither violence by domestic hate groups nor Islamic jihad are as deadly as non-ideological violence.

“We have over 14,000 murders each year and violent extremism accounts for far less than one percent,” he said. “We’re living in relatively peaceful times, but you get the impression from news reports on extremism that the threats are higher than they’ve ever been.”

In a New York Times op-ed published two days before the church attack in Charleston, Kurzman and Schanzer noted that the media's excessive focus on Muslim extremism comes with a social cost, writing that this attention “does a disservice to a minority group that suffers from increasingly hostile public opinion."

But Levin suggests that the price of inattention to the jihadist threat could prove far greater. “It’s almost like saying, there’s been no earthquakes in California, so California doesn’t need to worry about earthquakes," he said.

Levin believes we are living in an age of “super terrorism,” where technology has enabled even individual extremists to execute mass casualty attacks.

Potok shares Levin’s concern. To illustrate the scale of destruction that even a small radical cell could achieve, Potok points to a narrowly averted attack outside Fort Worth, Texas, in 1997. There, three Ku Klux Klan members planned to blow up a natural gas plant as a diversion for a simultaneous armored car robbery. If the local Klan leader hadn’t gotten cold feet and reported the plan to the FBI, authorities believe as many as 30,000 might have been killed.

“Ultimately, our biggest threat is whoever the heck is operational tomorrow,” said Levin. “And we just don’t know who that is.”