While not as large as in many other Western
countries, ISIS-related mobilization in the United States
has been unprecedented.
As of the fall of 2015, U.S.
authorities speak of some 250 Americans who have
traveled or attempted to travel to Syria/Iraq to join the
Islamic State in Iraq and Syria (ISIS) and 900 active investigations
against ISIS sympathizers in all 50 states.
Seventy-one individuals have been charged with
ISIS-related activities since March 2014. Fifty-six have
been arrested in 2015 alone, a record number of
terrorism-related arrests for any year since 9/11. Of
The average age is 26.
86% are male.
Their activities were located in 21 states.
51% traveled or attempted to travel abroad.
27% were involved in plots to carry out attacks on
55% were arrested in an operation involving an
informant and/or an undercover agent.
A small number of Americans have been killed in
ISIS-related activities: three inside the U.S., at least a
The profiles of individuals involved in ISIS-related activities
in the U.S. differ widely in race, age, social class,
education, and family background. Their motivations
are equally diverse and defy easy analysis.
Social media plays a crucial role in the radicalization
and, at times, mobilization of U.S.-based ISIS sympathizers.
The Program on Extremism has identified some
300 American and/or U.S.-based ISIS sympathizers active
on social media, spreading propaganda, and interacting
with like-minded individuals. Some members
of this online echo chamber eventually make the leap
from keyboard warriors to actual militancy.
American ISIS sympathizers are particularly active on
Twitter, where they spasmodically create accounts that
often get suspended in a never-ending cat-and-mouse
game. Some accounts (the “nodes”) are the generators
of primary content, some (the “amplifiers”) just retweet
material, others (the “shout-outs”) promote newly created
accounts of suspended users.
ISIS-related radicalization is by no means limited to
social media. While instances of purely web-driven,
individual radicalization are numerous, in several cases
U.S.-based individuals initially cultivated and later
strengthened their interest in ISIS’s narrative through
face-to-face relationships. In most cases online and
offline dynamics complement one another.
The spectrum of U.S.-based sympathizers’ actual involvement
with ISIS varies significantly, ranging from
those who are merely inspired by its message to those
few who reached mid-level leadership positions within