The face of terrorism is changing in the United States as the country comes to terms with the rising threat of "homegrown" terrorists who look and sound nothing like Hollywood typecasts.
A tall, fair-skinned American named David Coleman Headley is set to plead guilty in a Chicago court Thursday to using his Western appearance as a cover while scoping out targets in India for the deadly 2008 Mumbai siege and plotting to attack a Danish newspaper.
Five middle class college students from Virginia were meanwhile slapped with terrorism charges in Pakistan Wednesday after being caught on their way to allegedly join up with Taliban-led militants fighting US and NATO troops in Afghanistan.
Colleen LaRose -- a blond, blue eyed Texan who converted to Islam and adopted the moniker JihadJane after meeting extremists online -- was charged with plotting an assassination in Sweden and seeking out new recruits in an indictment unsealed this month.
LaRose's transformation is "one of our worst nightmares playing out," said Jerrold Post, author of "The Mind of the Terrorist" and director of the political psychology program at George Washington University.
"Individuals carrying American, British, French, any European passport who are indistinguishable from other citizens and who have been somehow radicalized... I have every reason to believe this will be increasing in frequency," Post told AFP in a recent interview.
US counterterrorism agencies are "concerned" about the influence of inspirational figures who reach out online to radicalizing new adherents, said Dennis Blair, the director of National Intelligence.
One such figure is Anwar al-Aulaqi, a radical imam who was born in New Mexico and is believed to be hiding in Yemen, Blair told a congressional hearing last month in his annual threat assessment last month.
Al-Aulaqi has been cited as an influence on three of the hijackers in the September 11, 2001 attacks and was in e-mail contact with Major Nadal Hassan, the army psychiatrist accused of opening fire at the Fort Hood army base and killing 13 people in November.
He has also been linked to a Nigerian student accused of trying to blow up a Detroit-bound flight with explosives in his underwear on Christmas Eve and Sharif Mobley, a New Jersey-born man arrested in Yemen this month on terror charges.
"Thus far, radicalization of groups and individuals in the United States has done more to spread jihadist ideology and generate support for violent causes overseas than it has produced terrorists targeting the homeland," Blair said.
"The tragic violence at Fort Hood last year underscores our concerns about the damage that even an individual or small number of homegrown extremists can do if they have the will and access."
Rising political tensions following the election of the nation's first black president combined with a lengthy and deep economic downturn has also led to the growth of other forms of domestic terrorism.
The number of extremist groups and armed militias which advocate radical anti-government doctrines and conspiracy theories nearly tripled last year to 512 from 149 in 2008, according a recent report by to the Southern Poverty Law Center, which tracks the activities of hate groups.
While the movement has not spurred any organized attacks like the 1995 Oklahoma City bombing that left 168 people dead, there have been a number of high-profile attacks by frustrated men who espouse radical anti-government views.
A mentally unstable California man opened fire on police officers outside the Pentagon earlier this month after apparently posting rants online about the "barbaric US government" and warning of a coming "new dark age."
A Texas pilot who was described by his friends as "easygoing" flew his single-engine plane into an Austin tax office last month after posting a rambling suicide note online describing his longstanding grudge against the government.
Prominent columnist Leonard Pitts said the Jihad Jane case -- along with other home-grown terrorists like former Chicago gang member Jose Padilla who was accused of plotting to detonate a 'dirty bomb -- shows how foolish it would be for counter-terrorism agencies to rely on racial profiling.
"Evil is an equal opportunity employer," he said.