A woman reacts at a makeshift memorial outside the Tree of Life synagogue following Saturday's shooting at the synagogue in Pittsburgh, Pennsylvania, October 2018.
A woman reacts at a makeshift memorial outside the Tree of Life synagogue following Saturday's shooting at the synagogue in Pittsburgh, Pennsylvania, October 2018.
Cathal McNaughton / REUTERS

On 9/11, 19 Arab hijackers trained in al Qaeda camps in Afghanistan killed almost 3,000 people in the United States in a matter of hours. It was the deadliest terrorist attack in U.S. history and has indelibly shaped Americans’ understanding of security and terrorism ever since.

Unfortunately, that understanding is increasingly out of step with reality. Jihadist organizations are no longer the main terrorist threat facing the country. Since 9/11, no foreign terrorist group has successfully conducted a deadly attack in the United States. The main terrorist problem in the United States today is one of individuals—usually with ready access to guns—radicalized by a diverse array of ideologies absorbed from the Internet.

The multilayered domestic threat was made tragically clear last week. A series of package bombs was sent to former U.S. President Barack Obama, the financier and philanthropist George Soros, and other critics of President Donald Trump. A racially motivated shooting at a grocery store in Kentucky, which killed two people, appears to have originated as a plan to attack a black church. And on Saturday, 11 people at a Pittsburgh synagogue were shot and killed by a man with an extensive history of expressing anti-Semitic and anti-refugee views on social media.

The recent attacks show that the most glaring terrorist threat facing the United States today is primarily domestic in nature. Ubiquitous firearms, political polarization, images of the extensive apocalyptic violence tearing apart societies across the Middle East and North Africa, racism, and the rise of populism have combined with the power of online communications to drive up violence across the political spectrum. 

Whether expressed in right-wing, left-wing, jihadist, or black nationalist ideological terms, today’s acts of political violence share a common lineage in the above mixture and together have resulted in almost 200 deaths since the 9/11 attacks. The death toll is even higher if one includes other deadly attacks with less traditionally political or clear motivations ranging from the new ideological misogyny of “incel” violence (incel being a term for a community of people who view themselves as involuntarily celibate and generally frame their perspective in ideological misogyny) to a spate of deadly school shootings. Addressing this threat will require a broad process of renewing U.S. society, a task far more difficult than disrupting a foreign terrorist organization’s operational capacity.


In the years since 9/11, groups such as al Qaeda, the Islamic State (or ISIS), and the Pakistan Taliban have demonstrated scant capacity to carry out operations in the United States. The last time any of these groups came close to successfully conducting its own deadly operation on U.S. soil was in May 2010, when Pakistan Taliban–trained Faisal Shahzad tried and failed to set off a car bomb in New York City’s Times Square.

ISIS-trained terrorists never succeeded in mounting a lethal operation in the United States. In one instance, ISIS did directly communicate via encrypted apps with individuals to plan an attack in Garland, Texas, in 2015 at a cartoon contest to draw the Prophet Muhammad. But the two perpetrators, Elton Simpson and Nadir Soofi, were both U.S. citizens who never traveled to an ISIS training camp. Both were killed by a security guard at the contest venue before they could launch their attack. 

Threats and concerns remain, of course, about the possibility of a foreign terrorist organization carrying out an attack on U.S. soil, but these are largely issues about managing a so-far-successful counterterrorism apparatus. Indeed, every lethal jihadist terrorist attack in the United States since 9/11 has been committed by a U.S. citizen or legal permanent resident. This runs counter to how Trump conceptualizes the threat, given his focus on keeping putative foreign terrorists out of the country. Trump’s travel ban was a solution to a problem that doesn’t really exist.


Jihad is a part of the new terrorist threat, but not in the way that Trump and many others believe. The danger largely comes from attackers inspired by jihadist ideology but not trained by or in direct communication with foreign terrorist organizations. These attackers have killed 104 people in the United States since 9/11, according to New America, a research institution that tracks political violence. Three-quarters of those deaths and eight out of the 13 deadly jihadist attacks since 9/11 occurred after ISIS began a sophisticated online messaging effort in 2014. It is this pitch and power to inspire that’s responsible for all of the deadly attacks tied to ISIS in the United States, not the group’s training camps and military forces in Syria, Iraq, or other conflict zones.

Far-right terrorism, such as the spate of attacks last week—including violence motivated by racial, anti-government, and anti-abortion political views—has killed 86 people since 9/11, according to New America’s research. The new threat, however, is not limited to the far right. In June 2017, James Hodgkinson, an individual with strong anti-Trump views, shot and gravely injured Representative Steve Scalise of Louisiana, the third-highest-ranked Republican in the House of Representatives. Individuals inspired by forms of black nationalist ideology have also killed eight people in two attacks over the past three years.

Meanwhile, attacks by perpetrators citing motivations that don’t quite fit traditional notions of political or terrorist ideology are also on the rise. In Toronto in April, Alek Minassian killed ten people in a vehicular ramming, having written of an “incel” rebellion. In a social media post, Minassian seemingly mimicked the form of pledges by ISIS attackers on Facebook. The United States saw an early case of this ideological misogyny when Elliot Rodger killed six people in 2014 near the University of California–Santa Barbara in a stabbing, shooting, and vehicular ramming attack, leaving a long manifesto. Minassian specifically referenced Rodger in his social media post.


Terrorism in the United States is still less common today than it was during the 1970s, when relatively organized groups and movements such as the Weather Underground carried out hundreds of bombings and hijackings. In 1975 alone, the Weather Underground claimed credit for 25 bombings. But that is not as comforting as it may at first seem. Many of the recent U.S. attacks have been the most lethal of their kind. The Pittsburgh shooting was the deadliest attack on Jews in American history, according to the Anti-Defamation League. The June 12, 2016, ISIS-inspired attack on the Pulse nightclub in Orlando by Queens-born Omar Mateen was the most lethal terrorist attack in the United States since 9/11.

This new terrorist threat cannot be addressed with an overwhelming focus on jihadist ideology.
Broader trends also raise the stakes. Trump has turned a blind eye to far-right terrorism, while some of his most prominent supporters such as Lou Dobbs and Ann Coulter have denied the existence of a right-wing threat. Right-wing media personalities and activists, including Candace Owens and even the president’s son Donald Trump, Jr., have peddled conspiracy theories regarding recent attacks. At the same time, politics, particularly on the right, is shifting into a more radical register. Recent public marches organized by the far right have resulted in violence, including the vehicular ramming that killed Heather Heyer during the Charlottesville “Unite the Right” rally last year. 

This new terrorist threat cannot be addressed with an overwhelming focus on jihadist ideology. Nor will a travel ban address a threat rooted in domestic politics and the Internet’s conveyance of global issues into American homes. Instead, today’s terrorist threat requires effective law enforcement, a real discussion of the dangers of lax gun laws, policies to regulate the ways social media has helped spread violence, community resilience, and a reckoning with the forces driving U.S. and global politics increasingly toward radicalism. 

Since 9/11, the U.S. government has been extraordinarily successful in disrupting foreign terrorist organizations’ ability to strike the United States. But the task of renewing and strengthening American society to face down the new terrorist threat could be even more difficult.

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  • PETER BERGEN is Vice President of Global Studies & Fellows at New America, a CNN National Security Analyst, Professor of Practice in the School of Politics and Global Studies at Arizona State University, and the author of United States of Jihad: Investigating America’s Homegrown Terrorists.
  • DAVID STERMAN is a Senior Policy Analyst in New America’s International Security Program.
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