Editor's note: Peter Bergen, CNN's national security analyst, is director of the national security studies program at the New America Foundation, a Washington-based think tank that seeks innovative solutions across the ideological spectrum, and the author of the new book "Manhunt: The Ten-Year Search for Bin Laden -- From 9/11 to Abbottabad." Jennifer Rowland is a program associate at the New America Foundation.  (CNN) -- On August 15, Floyd Lee Corkins allegedly walked into the Family Research Council in Washington, a conservative think tank, and shot the building manager Leo Johnson in the arm, saying something along the lines of, "I don't like your politics," as he did so.  Despite his gunshot wound, police say, Johnson was able to tackle Corkins and wrestle his weapon away before he could harm anyone else. (Corkins pleaded not guilty when he was indicted.)  Corkins was volunteering at a Washington community center for lesbian, gay and transgender individuals and his parents said their son had "strong opinions with respect to those he believes do not treat homosexuals in a fair manner." The Family Research Council promotes the view that homosexuality is harmful to society.  Three years earlier, also in Washington, rabid anti-Semite James von Brunn was charged with shooting and killing Holocaust Museum security officer Stephen Johns. He died while in custody.  Opinion: After 9/11, how we honored our son's memory  The shootings at the Holocaust Museum and Family Research Council underlined the fact that acts of political violence against civilians, commonly referred to as terrorism, can be carried out by those espousing many different types of ideology.  In fact, since the terrorist attacks that killed nearly 3,000 people at the World Trade Center and Pentagon 11 years ago, 19 people have died in terrorist attacks in the United States that were motivated by ideologies that have nothing to do with the ideas of Osama bin Laden, but rather were the victims of terrorists motivated by extreme anti-government views or virulent anti-Semitic/neo-Nazi views.  Jihadist terrorists, on the other hand, have killed 17 people, according to data compiled by the New America Foundation from thousands of news reports and court documents. ("Jihadist" terrorists are defined in this database as those associated with or motivated by al Qaeda, or its affiliates or like-minded groups.)  There have been 10 deadly attacks in the United States by nonjihadist extremists since 9/11 compared to just four by jihadists. (One of those incidents was at Fort Hood, Texas, in 2009 in which 13 were killed.)  The New America Foundation study suggests that law enforcement's tendency to regard Muslim-American communities as the most likely source of terrorism risks missing the threat from other extremists.  Since 9/11, jihadist and nonjihadist terrorists have killed about the same number of people in the United States, yet 61% of the 337 people indicted for terrorism-related activities since the 9/11 attacks are jihadists, according to the New America Foundation data.  Revisiting the mosque at Ground Zero  Since 2009 and 2010 there has been a sharp drop in the number of jihadist defendants, which peaked at 43 and 34 respectively. This year the number of jihadist defendants has dropped to 7, suggesting that the threat from these kinds of terrorists is receding.  The spike in jihadist terrorism defendants in 2009 and 2010 was itself largely due to the indictment of a ring of men in Minneapolis conspiring to send themselves and others to Somalia in order to fight on behalf of the al Qaeda linked militant group al-Shabaab.  Nine of the 43 jihadists indicted in 2009 were involved in plans to send fighters to Somalia, and 18 of the 34 jihadists indicted in 2010 were also part of this network.  U.S. authorities have recently come under fire for purportedly discriminatory counterterrorism tactics, such as the unjustified monitoring of mosques and cafes frequented by Muslims and the inclusion of language in FBI documents and textbooks that stereotypes or presents factually incorrect information about Muslims.  Of course, 9/11 rightly brought great law enforcement focus on possible jihadist terrorists. But the New America Foundation's data tends to support the view that law enforcement is more likely to target suspected Muslim militants than other extremists.  Although authorities are just as likely to use information provided by a confidential informant in the investigation of both jihadist and nonjihadist terrorist suspects, they are far more likely to place an undercover agent with a suspected jihadist terrorist suspect than a right-wing or left-wing extremist. An overwhelming 78% of the terrorism-related indictments that relied on an undercover agent were jihadist cases.  Of the 16 people who have been indicted since 2001 on terrorism-related weapons charges after some sort of sting operation in which the weapons were provided by the U.S. government, 75% were jihadists.  Yet the data indicates that nonjihadist terrorists are actually much more likely to have acquired weapons. Since 2001, 64% of the 127 people indicted on terrorism-related weapons charges were nonjihadist terrorists, such as Isaac Aguigui, one of four U.S. Army soldiers indicted in June for allegedly amassing $87,000 worth of guns and bomb parts that they planned to use in terrorist attacks against their home base of Fort Stewart, Georgia, and a park in nearby Savannah, Georgia.  Belief: Atheists continue battle against World Trade Center cross at memorial  Just last month, seven people, including two with links to the militant anti-government Sovereign Citizens movement, were indicted in connection with the shooting of four police officers in LaPlace, Louisiana, two of whom were killed. Authorities say Brian Smith allegedly opened fire with an assault rifle on a policeman directing traffic, and then led cops on a high-speed chase that ended at a trailer park, where others were waiting. The two officers were killed in the ensuing gunfight. (Smith has pleaded not guilty.)  Additionally, the New America Foundation found that no jihadist terrorists have acquired or even attempted to acquire chemical and biological weapons since 9/11, while 11 anarchist, white supremacist or right-wing extremists have been indicted for possessing such materials, and another four were indicted for attempting to produce them.  Some politicians and much of the public continue to believe that the threat from terrorists comes from violent jihadists, when in reality far-right extremists pose as much or possibly even more of a threat, something that we would do well to consider on the 11th anniversary of 9/11.  (Thanks to Megan Braun, Fatima Mustafa, Farhad Peikar, and Umar Farooq for their research help.)
Peter Bergen says it's a mistake to view terrorism in the U.S. solely as the product of jihadist groups