Digital dementia has to be the plague of our age, and this is surely its worst symptom:
"Before the Charlie Hebdo attacks in Paris in January 2015, Adel Kermiche was a cheerful, music-loving and devout French teenager. But that terrorist atrocity, and the suspicion-filled aftermath, 'acted like a detonator', his mother said. Soon his greatest wish was to join the so-called Islamic State, which his mother said had 'bewitched' him on social media. '[After Charlie Hebdo] he said we could not practise our religion in peace in France,' Kermiche's mother said. 'He was speaking with words that did not belong to him. He was bewitched, like he was in a cult'." (Normandy church attacker 'bewitched' by IS, Nick Miller, Sydney Morning Herald, 28/7/16)
A useful guide to the phenomenon (and much else as regards IS) is Abdel Bari Atwan's Islamic State: The Digital Caliphate (2015). Here are the opening paragraphs to chapter 1: Masters of the Digital Universe:
"Islamic State could never have achieved its territorial ambitions, nor could it have recruited such a large army in so short a time, without its mastery of the internet.
"Al-Qa'ida was the first major jihadist network to sense the potential of the worldwide web, using its darker recesses in a covert manner to share ideology, information, plans and correspondence. Its younger operatives also launched early cyber attacks on 'enemy' websites, presaging the emergence of the 'cyber jihad' that is raging today.
"Today, Islamic State and its supporters use the internet and social networking platforms in a brazen, overt way, marketing their 'brand' and disseminating their material in mainstream networks such as Twitter. For those already in the territories of Islamic State, as much as for potential recruits on their laptops in a thousand bedrooms across the globe, concealing identity and location remains a priority. But there are myriad ways this can be done. Advice on the wide range of 'anonymity products' available online is freely available for those who seek it - much of this advice is produced by Islamic State recruiters for the would-be jihadist. Those who fail to ensure their online anonymity are those we see detained and prosecuted. Sadly, this is only a tiny minority." (p 9)