What do the young British men who travel to fight, and possibly die, for Islam read before hitting the road? Well, in the case of Yusuf Sarwar and Mohammd Ahmed - both 22 years old and from Birmingham and who recently pleaded guilty to terror charges in the UK following a spell in Syria - the jihadist’s reading list is: Islam for Dummies and The Koran for Dummies.

The two set off for Syria in May 2013, spending eight months in the war torn country, fighting alongside Islamic extremists. While there, Ahmed relayed instructions on how to reach the battlefield – through Turkey – to a woman in the UK, who was subsequently detected when she unwittingly passed the information on to an undercover police officer.

Sarwar and Ahmed returned to the UK in January, encouraged to return by their concerned families. They were arrested at Heathrow on their return and, despite initially claiming they had travelled to undertake humanitarian work, soon admitted preparing to carry out terrorist attacks. They are now awaiting sentence.

In court the details of their plan emerged, including that the pair had bought Islam for Dummies and The Koran for Dummies before travel. Presumably the religious theory aspect of the Islamic State entrance exams is accommodating to those still getting to grips with the watered down basics of the religion they wish to kill and die for.

The involvement of young British men in the Islamic State’s (IS) war in Syria and Iraq has been thrown front and centre this week with the publishing of the video of the execution of American journalist James Foley. The man who murdered Foley speaks to the camera with a southern English, perhaps London, accent. An American journalist, executed by a British man fighting for a multi-national, stateless army waging a holy war in the lawless lands between Syria and Iraq. A problem borne of the age of globalisation and one that everyone – from politicians to the wider public – seem unable to properly comprehend, let alone adequately address.

Estimates of Britons fighting for IS range from 500 to 2000. If the latter figure – strongly disputed as it is – were true, it would mean more British men have signed up to fight for IS than the British Army. Taking either figure as accurate we can estimate somewhere between just 0.015 and 0.7% of the total British Muslim population has taken up arms to fight the West.

The debate over European born Muslim men going to fight in the Middle East has been run through repeatedly in the last few days, including discussion of the prevalence of Irish born fighters in the wars of the Middle East – although the initial reports of this may have been somewhat misleading of the true scale of the issue here. There have been no reports of any Irish citizen fighting for the Islamic State. Fear of a rapidly evolving, global menace seems to grow with each story of a Western born young man committing atrocities in the name of Allah. But to what extent is the role of religion given disproportionate weight at the expense of examining the myriad of other factors that influence young men to take extreme measures in their lives?

The Amazon shopping baskets of the Ahmed and Sarwar provide perhaps the best illustrative example yet that the siren luring thousands of young Muslim men to the call of martyrdom and fanatical, fundamental holy war is not the teachings of a religion, but something else. Something both societal and internal. It also warns us that categorising religious devotion as the core motivator may be to drastically misdiagnose the problem.

Mehdi Hasan, who brings us the news of the pair’s pre-jihad study curriculum, and proposes a strong argument against laying the blame for radicalisation at the door of Islam, comments that:

“The swivel-eyed young men who take sadistic pleasure in bombings and beheadings may try to justify their violence with recourse to religious rhetoric – think the killers of Lee Rigby screaming “Allahu Akbar” at their trial; think of Islamic State beheading the photojournalist James Foley as part of its “holy war” – but religious fervour isn’t what motivates most of them.”

Daniel Hannan makes the point in the Telegraph that:

“One observation made by almost all the experts who have studied Western-born Islamic militants is that they fit the classic profile of the terrorist down the ages: male, typically in their twenties or early thirties, with some education, narcissistic, lacking in empathy, lonely, unsuccessful with women, often with a history of petty crime.”

Hasan points us towards the excellent Chris Morris satirical comedy ‘Four Lions’ as one of the best ways of understanding home-grown holy war. The story of a group of ignorant, incompetent British Muslims who plan jhad on the streets of Britain is superb entertainment and excellent comedy, but it’s underlying message is best summed up by Morris when he says: “Terrorism is about ideology, but it’s also about berks.”