A glance at what is known about the ISIL terrorists involved in the November 13 Paris attacks reveals a classic path of recruitment.
There is no evidence in their profiles of higher education, vocational qualifications or the potential to do well in life. Most grew up in poor immigrant areas and many had criminal records.
But recent successes of extremist groups in attracting volunteers include more examples of the enlistment of apparently intelligent young men and women who are, or were, exemplary students with bright futures.
“We are talking about people who may be very smart in a worldly way but stop being smart when it comes to the emotional sense,” says Alyas Karmani, who runs an anti-radicalisation project, Street, in London and Bradford, a northern English city that is home to a large Muslim community.
“They might be doctors or other professionals but have only basic theological understanding and are easily blinded by ISIL’s messianic perspective, the idea of Armageddon and the mother of all battles to come.”
As the British government launches controversial initiatives to counter extremism, including a threat to deport Muslim immigrants if they fail to learn English, Street is one of a number of organisations urging a more imaginative approach.
Two days after the UK prime minister David Cameron outlined his plans, Britain’s Channel 4 screened a documentary on two activists campaigning for Sharia to be enforced in the UK.
Mohammed Shamsuddin and Abu Haleema operate on the fringes of legality, refusing to express public support for ISIL, which would make them liable to imprisonment.
Both are associates of, and speak highly of, Abu Rumaysah, the British former bouncy castle salesman who appears in a recent terrorist clip showing the murders of five captives in Syria.
In the Channel 4 documentary, Shamsuddin and Haleema are seen laughing inanely while watching a so-called ISIL "execution video".
It seems beyond belief that academically gifted young Muslims, often from comfortable homes, could be swayed by the slogan-laden, barely coherent ramblings of such men, let alone wish to engage in a cause that glorifies acts of savagery.
But Mr Karmani says this overlooks the alarming “desensitivisation” of a generation that has become accustomed to images of violence on social media.
“ISIL gives them something to believe in when they feel disenfranchised by the system,” he says.
“Every legitimate Islamic scholar condemns them. But while ISIL has no scholarship, it does have powerful communications.”
Among a number of well-documented cases of educated recruits is that of 17 British Muslim doctors and medical students who travelled in two groups from Sudan to join ISIL’s medical operation in Syria last year.
All were attending Khartoum’s University of Medical Sciences and Technology (UMST), prompting Britain’s foreign ministry to send a delegation, including an imam, to work with Sudanese authorities to stop further departures.
A key figure in this recruitment channel was Mohammed Fakhri, 25, an imam’s son from the north-eastern English town of Middlesbrough. He previously ran UMST’s Islamic Cultural Association, now disbanded.
Fakhri’s whereabouts is unclear. Media reports say his last known public gesture was an essay aimed at winning over “hesitant” supporters.
While the ideology he champions is widely rejected by respected Islamic scholars, he is shown to be an articulate figure with the persuasive skills that make him a dangerous recruiting sergeant.
British newspaper The Observer has speculated that Fakhri is specialised in the enlistment of women, perhaps reassuring them they would be exempt, as medical recruits, from ISIL's reactionary policies on female employment.
Seven British Muslim women are reportedly among the medics, qualified doctors or at an advanced stage of medical studies, who left from Khartoum to work in areas under ISIL control.
They include Lena Mamoun Abdel Gabir, 19, a daughter of doctors who is remembered at her old school as being “ferociously bright, engaged and focused on her academic studies”.
In a Twitter message last year before joining ISIL, Gabir wrote: “You know times are rough when your dad calls you khawarij [rebels disowned by Islamic scholars] and your mum keeps referring to you as daesh [ISIL]”.
Hanif Qadir has, from painful personal experience, part of the answer as to why bright, thinking young people can become sucked in by extremist propaganda.
Now the head of Active Change Foundation, a London-based anti-radicalisation organisation, and author of an imminent book, Preventing Extremism and Terrorist Recruitment, Mr Qadir was briefly an extremist sympathiser.
In 2002, after the previous year’s September 11 attacks in the United States and the military intervention in Afghanistan that followed them, he became part of a network of Al Qaeda members.
Despite having a garage business and financial stability, he travelled to Afghanistan to join “the cause”.
However, he soon fell out with the Taliban after concluding that young men and women were “being used as cannon fodder in a war that many people knew little about”.
He says of his brush with radicalisation: “It was quite a roller-coaster journey.
“You get led to another point and a state of mind in which you don’t think rationally and can even become willing participants.”
He believes ISIL is able to achieve conversions because it is better at indoctrinating people, impressing them with its “agenda, objectives and narrative”, than officials are at countering its message.
Even someone who knows little or nothing about its cause and may not even be a Muslim can be open to conversion, Mr Qadir says, with personal friendships being a “powerful dynamic”.
“If you are passionate about something and really want to do something, you go to friends and get them to support you,” says Mr Qadir, who is dealing with several cases of young white Britons from Christian or atheist backgrounds being lured by ISIL propaganda.
Luqman Ali, a London imam and director of Khayaal, a theatre company that adapts previously unperformed Muslim literature for stage screen and radio, went twice to Sudan as part of the UK government’s mission to deter medical students from extremism.
He encountered a common view of “it could have been me” when talking with western Muslim students about those who joined the extremists. The students, he says, often had little experience of the world beyond home and school and in some cases were reluctantly studying medicine under parental pressure.
Mr Ali warns against the “easy categorisation” of recruits, citing underlying factors common to all and arising from complex issues of “multiple internal conflicts of identity, and the search for significance, purpose and belonging”.
He says the vulnerability of Muslim youth to extremist narratives is inadvertently created by the West treating Islam and Muslims as “the other” while lacking the “courage, imagination and ethical compass” to forge a positive, postcolonial self-definition.
Mr Ali’s words echo those of a British commission on religion and belief in public life.
The commission, chaired by retired senior judge Lady Elizabeth Butler-Sloss, wants major national and civil events, including coronations, to adopt a more pluralist character to reflect changing society.
“In framing counter-terrorism legislation, the government should seek to promote, not limit, freedom of enquiry, speech and expression, and should engage with a wide range of affected groups, including those with which it disagrees, and also with academic research,” the commission says.
“It should lead public opinion by challenging negative stereotyping and by speaking out in support of groups that may otherwise feel vulnerable and excluded.”
Academic achievement and potential for professional success are not always sufficient to overcome a sense of exclusion – and the magnet of a violent cause with advanced social media skills.