In a room deep in the bowels of New Scotland Yard, a graph is pinned to the wall. It shows a gently rising flat line that suddenly shoots up almost vertically. Closer inspection reveals a series of labels: the first is 'empathetic', the next 'sympathetic' and then, finally, 'o'.
The 'o' stands for 'operational', the moment when someone moves from being sympathetic to al-Qaeda to carrying out an atrocity in its name, the point where the graph shoots up.
What makes someone take that step? What makes someone want to turn themselves into a human fireball and ram a Jeep into an airport terminal building? What makes someone want to maim and kill? The answers remain the disputed domain of psychologists and sociologists. But what counter-terrorism officials know for sure is that the speed with which individuals, men, usually young, move from being sympathetic to an idea to actually wanting to carry out an attack is becoming faster. And as the curve on the graph gets shorter, the police are becoming more alarmed.
'Based on information from Canadian intelligence we believe the shortest time it's taken someone to go to operational is one and a half weeks,' said one person familiar with the study.
It is not just the security services who ponder the graph. Officials in the Department for Communities and Local Government - the official body charged with improving community cohesion - are also hypnotised by 'the bell curve prevention strategy'.
'We've got to focus on the left of the graph, start building relevant approaches to stop people moving from empathetic to operational,' said Haras Rafiq, of the Sufi Muslim Council, a body that represents a number of mosques in Britain.
'There may be a catalyst, something that causes someone to go operational, such as, say, giving a knighthood to Salman Rushdie,' Rafiq said. 'But the vehicle is ideology, the theological justification that powers the bell curve. You've got to address the ideology.'
Kafeel Ahmed is unlikely to make it. With 90 per cent burns, he lies in the Royal Infirmary in Glasgow, unconscious and attached to a multitude of drips and wires. No one survives such extensive injuries. All his family back home in Bangalore can do is pray to Allah.
A doctor of technology who studied at the Anglia Ruskin University, Ahmed was a respected member of his faculty. He had interests in aerodynamic design, electronic maps and inkjet cartridges, producing a seminal paper on the latter subject which earned him plaudits in the university's annual report.
Ahmed was one of the two men who tried to drive a Cherokee Jeep into Glasgow airport eight days ago. Witnesses said that after the Jeep was stopped by security bollards he appeared to smile as he doused himself with petrol before setting himself alight while crying 'Allah'. Soon after this self-torching, Ahmed's brother, Sabeel, was arrested in Liverpool, a short commute from the Warrington hospital where he worked as a doctor.
The Glasgow attack sent shockwaves through Britain. Coming just two days after the discovery of two Mercedes packed with propane and nails in London's West End, it had a surreal, nightmarish feel.
Astonishingly, as events unfolded and arrests were made across Britain and in Australia, detectives quickly came to believe the Glasgow attack was carried out in haste by two of the men behind the botched attempt to blow up London's West End. One of the men, Billal Abdullah, has now been charged with conspiracy to cause explosions.
Kafeel Ahmed has not been charged. 'You can't charge the unconscious,' one security source observed. But Ahmed, who is suspected of using his engineering expertise to turn the two Mercedes into bombs detonated by mobile phones, appears to be the glue that binds many of the suspects together.
It was Kafeel who introduced Sabeel to Mohammed Asha when he came to visit him in Cambridge. Asha, a 26-year-old neurosurgeon who lives in Staffordshire, has Palestinian parents but grew up in Jordan. A brilliant student, he attended a school for gifted children in Amman. Asha, along with his 27-year-old wife, Marwah, a laboratory assistant, was arrested while driving on the M6 shortly after the attack in Glasgow. Their parents have expressed astonishment at their arrest and believe that they will be released without charge.
The Ahmed brothers are also the second cousins of Dr Mohammed Haneef, who was arrested in Australia. Like the brothers, the 27-year-old studied in Bangalore before becoming a doctor at Halton hospital in Cheshire and then moving to Australia's Gold Coast. Australian police are reportedly in possession of tapes of Haneef discussing suicide bombings. Two other men, both believed to be Saudis and also trainee doctors, have also been held and one man has now been charged, bringing the total number of suspects to eight. Seven are doctors.
The Ahmed brothers attended a respected school in Bangalore but later fell under the influence of Tablighi Jamaat, the Islamic sect described by French intelligence as the 'ante-chamber of Islamic fundamentalism'. Tablighi Jamaat insists it is a peaceful movement but its emphasis on the Deobandi interpretation of Islam has come under close scrutiny in Britain after it emerged two of the London 7/7 bombers were linked to it.
Security officers and sources within Ireland's Islamic community have confirmed Kafeel Ahmed was a well-known associate of Abbas Boutrab, an al-Qaeda explosives expert currently being held in Maghaberry prison, Co Antrim.
Ahmed lived in Northern Ireland between 2001 and 2004 while studying at Queen's University for an MPhil in aeronautical engineering. At Queen's he was a member of the Islamic Student Society which took part in multi-faith gatherings, according to Jamal Iweida of the Belfast Islamic Centre. He said the Centre was 'shocked and astonished' that one of their former members could have been involved in last weekend's terror attacks.
Ahmed's alleged links to Boutrab could be highly significant as the security services attempt to gauge the role of al-Qaeda in the failed attacks in London and Glasgow. The Algerian-born terrorist was convicted at Belfast Crown Court three years ago for possessing information likely to be of use to terrorists. These included instructions on how to build bombs that could destroy airliners. Last year it emerged Boutrab built a home-made bomb while in prison.
In the quiet, leafy streets around the Cambridge Mosque on Mawson Road, the only one in the ancient university city, several of the suspects arrested last week used to be a familiar sight. They were often seen attending Jumah, Friday prayers. Abdul Kayum Arain, co-ordinator of Cambridge Muslims Online, an internet forum, and a regular visitor to the mosque, said the men were always pleasant when he met them.
But someone who encountered one of the suspects on several occasions while in Cambridge four years ago recalls a different side. 'He was angry, even back then,' the person, who asked not to be named, said. 'He told Muslims they shouldn't vote, he was always the "white man this, the white man that".'
While some mosques have earned notoriety in recent years, the Cambridge mosque is considered an inclusive role model, an institution that sits comfortably in its community. One of its imams, Timothy Winter, a respected academic in Cambridge, was a member of the government-sponsored roadshows commissioned to reach out to disaffected Muslim youth in the wake of the 7/7 bombings. 'The mosque's teaching is always that we are all children of God,' Arain said.
And yet, despite such teaching, it is alleged some of the suspects still became radicalised. The question is: by what? Friends recall one of the men was preoccupied by the West's wars in Iraq and that the issue of Palestine was never far from his thoughts. Shiraz Maher, a former member of the radical group Hizb ut-Tahrir knew one of the men and recalled how he would cheer news of British and American deaths in Iraq.
Security services are investigating claims that some of the men attended 'outward bound'-style bonding exercises in Cumbria, Scotland and possibly Tunbridge Wells in Kent.
Several of the suspects crossed the security services' radar after making mobile phone calls abroad or accessing jihadi websites; there have been claims that one was facing disciplinary action for the amount of time he was spending in front of computers at work. Security sources said this did not mean that any one of them was under surveillance.
The role of the internet in perpetuating terrorism was emphasised last week in two separate court cases. Omar Altimimi was jailed for possession of manuals on how to carry out car bombings, many of which were downloaded from an al-Qaeda website accessed by a password.
In a separate case, three men who used the internet to urge Muslims to carry out their 'religious duty and wage holy war against non-believers' were jailed. Ringleader Younes Tsouli, who ran an internet site which regularly featured beheadings, was sentenced to 10 years. Police investigating the case unearthed online forum discussions involving a group of 45 Muslim doctors in the US who threatened to use car bombs and rocket grenades in terrorist attacks in their home country.
Ultimately, though, it seems the suspects' main influences came from overseas groups, the Deobandi and Wahhabi sects that have flourished in Saudi Arabia and Pakistan thanks to their anti-Western message and their emphasis on sharia law. One prominent Wahhabi cleric, Ahmed al-Qubeisi, who advocates suicide bombings and the right of a man to beat his wife, is believed to have been a hero to at least one of the plotters.
Currently almost 100 terror suspects are awaiting trial in UK courts in about 40 separate cases and the number will rise. Just before retiring as director general of MI5 last April, Dame Eliza Manningham-Buller detailed her concerns for the future, leaving her successor, Jonathan Evans, in no doubt as to the scale of the challenge posed by al-Qaeda. She warned the 'UK is a centre of intense activity' and that there is a 'very real possibility' that al-Qaeda and groups linked to it are planning a nuclear attack.
The investigation is going global with requests for intelligence sent to the US, Canada, Pakistan, India, France, Australia and Ireland. Proven links to other cells could indicate the guiding hand of a senior al-Qaeda figure, something the security services accept is a real possibility. 'Usually there is one charismatic person at the centre of all this who exerts an influence over the others,' a security source said.
The question that has echoed across Britain this past week is whether a group of highly educated doctors could be capable of mass murder, an egregious inversion of the Hippocratic oath.
Terrorism experts point out that all the members of the Hamburg cell, which planned the 9/11 atrocities, studied technical sciences or medicine. Abdullah Azzam, the original mentor of Osama bin Laden, was a Palestinian medical doctor. Ayman Al-Zawahiri, the spiritual leader of al-Qaeda, comes from a family of doctors and medical experts.
That educated men could be just as likely - if not more likely - to commit acts of terror sits at odds with the conventional 'old world' view of terrorism. As Professor Marc Sageman, a counter-terrorism adviser to the US government observes: 'Terrorists are usually seen as being ignorant and immature, as coming from a poor background and a broken family, with no skills and no family or responsibility. Little of this is true for al-Qaeda members and supporters.'
Dr Irfan al-Alawi, director of the Centre for Islamic Pluralism, has just completed a 130-page report into the links between radical Islam and science.
'In our study we have documented notable cases where the phenomenon of radical Muslim doctors is well known,' he writes. 'These individuals suffer from divided minds, in which their professional duties clash with their ideological fantasies. They are driven not by faith, or by training, or by professional standing or aspiration, but by an ideology of fundamentalist separatism.'
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