
NCTC assesses that the Sunni violent extremist threat in the US has evolved from one defined by complex, large-scale attacks directed by a foreign terrorist organization (FTO) to mostly self-initiated attacks by homegrown violent extremists using relatively simple methods. Of the 28 Sunni violent extremist attacks in the US since 9/11 only three were directed by an FTO. Most attacks were perpetrated by individuals enabled—through encouragement or operational support—or inspired by ISIS, al-Qa‘ida, and al-Qa‘ida affiliates.