How Islamist Terror Threats Have Evolved Since 9/11

The terror attacks of September 11, 2001, marked the opening of a new era: one in which physical attacks by Islamist extremists would become a recurring reality on American soil. The hateful ideology that drove the hijackers would outlive them, spreading, splintering, and continuing to inspire violence globally for decades to come.

Though the United States has been spared another terrorist attack on the scale of 9/11, Islamist extremism has not been defeated. It has metastasized and adapted. Hundreds of recent attacks and foiled plots in the United States since 9/11 exemplify the persistence of this threat.

The ADL Center on Extremism has identified at least 142 terrorist incidents in the United States from 2002 through the first half of 2026 that were associated with Islamist extremism. At least 19 people have been killed in Islamist terror incidents in the United States in the past two years alone.

Tactics have evolved. The perpetrators and planners of 9/11 were operating under the leadership of Osama Bin Laden, who established al-Qaida with the goal of establishing a worldwide Islamic caliphate through violent jihad. The group established the modern model of an international, pan-Islamist terrorist organization, ready and willing to use modern technology and communications to further their ideological aims.

The Islamic State of Iraq and Syria (ISIS), an offshoot of the group that emerged around 2011, quickly made use of sophisticated social media networks to spread their violent ideology. The group published glossy online propaganda in a dozen languages, spread through decentralized systems of file sharing, archival sites, and encrypted messaging applications. The group’s graphic videos have more recently gained traction in online gore forums — and likely contributed to inspiring others to pursue similar acts of terror.

It doesn’t take formal training or in-person contact with a terrorist cell to inspire violent acts. Islamic State's technological fluency has allowed the terrorist group to survive and inspire attackers internationally even after the loss of its geographic stronghold in 2017.

Islamist terror incidents in the United States decreased considerably by the end of the 2010s. But there has been a notable uptick in Islamist extremist terror incidents, both foiled plots and actual attacks, since 2024. From three incidents in 2023, the number rose to eight that year. Five more incidents occurred in 2025, while another five have already been documented as of September 8, 2026.

Three men were arrested in Dearborn, Michigan, in 2025 for allegedly conspiring to provide material support to ISIS and for having firearms that would be used to commit an act of terrorism on behalf of the group. At least one of them, according to research conducted by the ADL Center on Extremism, watched videos on the gore website WatchPeopleDie.

A young man in North Carolina and another in Texas were likewise both charged in 2025 with terrorism-related offenses for allegedly actively working toward violent Islamic State-inspired attacks on American soil.

Of the 10 Islamist extremist incidents in the United States from 2025-2026, seven notably involved lone perpetrators. Lone perpetrators — harder for law enforcement to identify and apprehend them before they can carry out their intended acts — were responsible for all four of the fatal incidents from those two years.

The violence and disdain for innocent life demonstrated by Islamist extremist groups continues to plague the United States. It has become deeply embedded in the violent ecosystems that fuel terrorist plots, school shootings, and the targeting of innocent people worldwide.  

2026 Incidents

• New York, New York, May 15, 2026. In an international terrorism incident, federal authorities charged an Iraqi citizen, Mohammad Baqer Saad Dawood al-Saadi, with multiple offenses, including conspiring to provide material support to terrorist groups and conspiracy to bomb a place of public use. Al-Saadi is allegedly a leader in the terrorist group Kata'ib Hizbollah, which has links to Hezbollah and the Islamic Revolutionary Guard Corps; he reportedly directed numerous terrorist attacks against U.S.-connected and Jewish-related targets in Europe and Canada. He also allegedly plotted to attack targets in the U.S., including a New York synagogue, paying thousands of dollars to someone he thought would carry out the attack.
• West Bloomfield, Michigan, March 12, 2026. Ayman Mohamad Ghazali, an American citizen of Lebanese origin, drove a truck into a Detroit-area synagogue, crashing through the entrance and into the building. Ghazali's vehicle struck a security guard, who was injured but survived the attack; Ghazali also exchanged gunfire with at least one other guard. More than a hundred children were attending classes at the synagogue at the time of the attack, but none were injured or killed. Ghazali had fireworks and containers of gasoline in his truck and apparently intended to set the building on fire after he rammed it, but he became stuck in his vehicle, which then itself caught on fire. Heavily burned by the fire, Ghazali killed himself. Four relatives of Ghazali had reportedly been killed during an Israeli airstrike in Lebanon during Israel's ongoing war against the terrorist movement Hezbollah; Israeli officials and journalists have said that two of Ghazali’s relatives were members of Hezbollah. According to the FBI, Ghazali often watched Hezbollah-related content online. Ghazali allegedly sent a video to another relative in Lebanon saying that he was at the synagogue and intended to kill as many people as possible.
• Norfolk, Virginia, March 12, 2026. Mohamed Bailor Jalloh opened fire at an ROTC classroom at Old Dominion University while yelling "Allahu Akbar," killing an ROTC instructor and wounding two students before being subdued and killed by other students in the classroom. Jalloh had been convicted a decade earlier for attempting to provide material support to a designated foreign terrorist organization, ISIS, and was sentenced in 2017 to 11 years in prison. He left prison in late 2024, subsequently taking online classes at Old Dominion.
• New York, New York, March 7, 2026. Federal authorities charged two men, Emir Balat and Ibrahim Kayumi, with using a weapon of mass destruction and attempting to provide material support to a foreign terrorist organization after the pair allegedly threw two homemade bombs at far-right anti-Muslim protesters holding a demonstration outside the residence of the mayor of New York City. The bombs failed to detonate. The two men reportedly told police after their arrest that they were inspired by ISIS.
• Austin, Texas, March 1, 2026. Ndiaga Diagne opened fire from his vehicle at a nearby beer garden-style restaurant, then drove a short distance, exited his vehicle, and began to shoot at passersby. Diagne killed three people and wounded 15 more before responding police shot and killed him. Diagne wore a sweatshirt during the attack that read "Property of Allah," as well as a shirt bearing an Iranian flag. A social media account believed by law enforcement to be connected to Diagne reportedly contained pro-Iranian, antisemitic, anti-Christian, and misogynistic comments; investigators searching his apartment after the attack found an Iranian flag and images of Iranian leaders. An FBI investigation update several days after the attack reported that there was "no evidence of outside direction or radicalization," but characterized the attack as a violent response to the then-recent attack on Iran by the U.S. and Israel.

2025 Incidents

• Mint Hill, North Carolina, December 31, 2025. On New Year's Eve, federal agents arrested Christian Sturdivant to prevent him from carrying out an alleged terrorist plot scheduled for the next day that reportedly involved stabbing people at a fast food restaurant and a grocery store. Sturdivant had originally come to the attention of the FBI in 2022, when he was only 14, for allegedly communicating with someone thought to be connected to the terrorist group ISIS. The FBI reportedly learned in December 2025 that Sturdivant had been posting pro-ISIS messages on social media and started a new investigation that eventually led to his arrest. However, despite the FBI having evidence that a federal judge described as "substantial and at times chilling," Sturdivant was charged only with providing material support to a foreign terrorist organization.
• Detroit, Michigan, October 31, 2025. Federal agents arrested Mohmed Ali and Majed Mahmoud, as well as a third man arrested soon after, Ayob Nasser, on charges of conspiring to provide material support or resources to a foreign terrorist group and receiving and transferring, and attempting and conspiring to transfer, firearms and ammunition while knowing and having reasonable cause to believe that the firearms and ammunition would be used to commit an act of terrorism. More people were also subsequently arrested, although at least some on charges seemingly unrelated to the plot itself. According to the criminal complaints, the alleged plotters, inspired by ISIS, conducted firearms training in preparation for an attack and scouted target locations that included LGBTQ+ bars and an amusement park.
• Boulder, Colorado, June 1, 2025. Mohamed Sabry Soliman, an Egyptian national living in Colorado, allegedly threw Molotov cocktails at people holding a peaceful walk in Boulder to bring attention to Israeli hostages then held by Hamas in Gaza. According to authorities, Soliman also brought a homemade flamethrower with him. The attack injured over a dozen people, including a Holocaust survivor. One 82-year-old woman who was also attacked died days later due to the severe burns she suffered. Arrested following the attack, Soliman allegedly told authorities that he had planned the attack for a year and wanted “to kill all Zionist people and wished they were all dead.” A social media account allegedly belonging to Soliman expressed support for the Egyptian Muslim Brotherhood. Colorado authorities charged Soliman with dozens of offenses, including first degree murder; in May 2026, he pleaded guilty to 101 charges and was sentenced to life in prison. He has also been charged with 12 federal hate crime allegations, which have yet to come to trial.
• Warren, Michigan, May 13, 2025. Federal authorities arrested Ammar Abdulmajid-Mohamed Said outside a military facility, charging him with attempting to provide material support and resources to a terrorist organization and distributing information related to a destructive device or explosive. According to authorities, Said sought to engage in violence either by traveling abroad to help the Islamic State terrorist group or by attacking a target in the U.S. Authorities also said he planned a mass shooting at the U.S. Army's Tank-Automotive and Armaments Command facility near Detroit and had even conducted surveillance on the target using a drone. As of this writing, Said is still awaiting trial.
• New Orleans, Louisiana, January 1, 2025. Shamsud-Din Jabbar bypassed barriers to drive a rental truck into a crowd of New Year's celebrators on Bourbon Street in New Orleans, an attack that left 14 people dead and dozens more injured. The suspect, who made videos prior to the attack in which he claimed to have joined the Islamic State terrorist group, had an Islamic State flag on his vehicle. Jabbar died in a shootout with law enforcement officers responding to the attack. Afterwards, police found two explosive devices in the vicinity of the attack, which surveillance video showed had earlier been placed by Jabbar, possibly intended to target civilians or first responders.