Domestic Islamist extremismDomestic Islamist extremism in the U.S.: 2018-2019
While white supremacists and other right-wing extremists are responsible for most extremist-related domestic murders committed in the past decade, terrorism and violence inspired by Islamist extremism continues to pose a serious threat to Americans. ISIS’s violent ideology continues to resonate with and radicalize U.S. citizens, but domestic Islamist extremists are increasingly seeking inspiration from other foreign terror organizations such as Al Qaeda. In 2018, 13 individuals were arrested for domestic criminal activity motivated by Islamist extremism — all of them were lawfully in the United States at the time of their arrest. The number of individuals arrested for domestic Islamist extremist criminal activity decreased from 2017 to 2018 by approximately 40 percent.
While white supremacists and other right-wing extremists are responsible for most extremist-related domestic murders committed in the past decade, terrorism and violence inspired by Islamist extremism continues to pose a serious threat to Americans. Threat assessments consistently evolve; any known threat is deserving of careful attention.
At the near-midpoint of 2019, Islamist extremism remains a concern. As of June, law enforcement has foiled five Islamist extremist inspired plots in the United States, including a plot to attack federal buildings in Washington D.C., carry out a vehicular ramming at the National Harbor in Maryland, attack a white supremacist rally in California, attack a pro-Israel rally and the Israeli consulate in New York, and detonate explosives in Times Square in New York. Internationally, ISIS successfully planned and executed one of its deadliest attacks to date, killing 253 and injuring 500 more on Easter Sunday in Sri Lanka.
These events underscore that relatively modest attack trends do not mean the threat from any particular extremist ideology can be discounted. As described throughout this report, overall attacks within the United States are down, but the pervasiveness of the ideology makes for a continued threat.
2018
In 2018, ADL documented 13 arrests related to domestic criminal activity motivated by Islamist extremism. Four of the 13 arrests were linked to terror plots. The targets included a high school student’s sleepover, a mall, a July 4th parade, and a synagogue. The remaining nine arrests involved individuals who allegedly attempted to provide material support to foreign terror organizations.
Compared to the 32 people arrested in 2017, the number of individuals arrested for domestic Islamist extremist criminal activity decreased in 2018 by approximately 40 percent. This slowing of activity is certainly notable, but it does not indicate that the threat of Islamist extremism in the United States has subsided. It is worthy of continued vigilance.
For a full and continuously updated list of domestic terror plots and attacks inspired by Islamist extremism, see ADL’s H.E.A.T. map.
