In the wake of the horrific events in France last week, much has been made of the fact that both suspects were known to the authorities. The same kind of things were said about the killers of Lee Rigby, and of Tamerlan Tsarnaev, one of the Boston bombers.
Of course, the fact that the authorities were aware these people existed and could potentially be a threat ultimately made little difference; they were all able to plan and execute attacks without security agencies cottoning on until the events had taken place.
This raises a couple of questions: Is the mass data mining of GCHQ and the NSA really that effective? And have those planning terror attacks changed their tactics now the whole world knows there's probably someone listening in on their every conversation? I checked in with some professional anti-terror types to find out.
Dr Steve Hewitt, a counter-terrorism expert at the University of Birmingham, provided a window into the effect the Paris atrocity has had on the security community. "There are short-term and long-term issues," he told me. "Short-term, the key is obviously not just to prevent future attacks, but also to anticipate what form these might take. The recent 'norm', if it can be called that, has been the 'lone actor' type attacks, including some experienced by France prior to Christmas. But now the concern is with what happened in Paris. However, this type of attack will probably remain more rare than the lone actor ones. First, there is the requirement of skill, time, planning and greater dedication, and, with multiple participants, an increased possibility of detection."
Not to appear too self-interested, but this did make me wonder whether there are any major differences between the threats present in France and those in the UK.
Dr Hewitt continued: "Significantly – and this is a key issue for me coming out of Wednesday – such attacks require weaponry. In the UK, obtaining weapons is not easy; and even if a weapon is obtained, getting access to ammunition is also no easy matter. Thus, having the aspiration to carry out an attack isn't sufficient if one does not possess the means.
"All of this means that lone actor attacks will likely remain the trend for the foreseeable future, which is generally a good thing because, although they're less likely to be detected, their ability to cause widespread casualties is also generally more limited. The long-term issue is to deter individuals from engaging in violent extremism, but determining how to do this and who to target is far from an exact science."
This issues of suspect detection and tracking bring up serious questions about intelligence agencies and how they operate. Over the past few years – certainly since the Ed Snowden revelations – discussions of counter-terrorism strategies have focused on government spying, and in particular on the indiscriminate collection of "big data", i.e. the NSA and GCHQ trawling through everyone's phone calls, emails and embarrassing browser histories.
There's been much debate about the civil liberties black hole these practices represent. Now it's time to figure out whether they even work.
I spoke to Dr Gilbert Ramsay, of the Centre for the Study of Terrorism and Political Violence at the University of St Andrews. His answer was pretty emphatic: basically, it's one thing to ask service providers to store data and then make it available to authorities so that they can conduct a focused enquiry based on pre-existing human intelligence leads. It's quite another thing to use it to actually uncover terrorists. "To my knowledge, all attempts at the latter have been unsuccessful, and sometimes laughably so."
This may be a slight understatement on Dr Ramsay's part. The question should really be: Does fighting terrorism with semi-legal metadata ever actually work?
When called to defend the NSA spying programme in front of a Senate Judiciary Committee, General Keith Alexander claimed that the agency's data mining had thwarted 54 terror attacks. But, on closer inspection, 53 of these claims turned out to be bullshit, and the General was left with only the case of Basaaly Moalin, a San Diego cab driver who, in 2008, managed to funnel just over £5,500 to someone affiliated with al-Shabaab.§
This is particularly pertinent in relation to what happened on Wednesday. The attack on Charlie Hebdo was, more than anything else, an attack on the idea of the open society. That idea is threatened as much by spying in the name of security as it is by the guns of bigoted idiots. And if the spying isn't even delivering the security – well, then they're just taking the piss.
Either way, if – as Dr Hewitt suggests – we're moving into an era of "lone wolf" attacks, counter terrorism through big data will become irrelevant by definition.
Hewitt went into some common-sense detail: "The smaller the number of attackers, the more difficult they are to detect," he said. "There's a greater awareness that movements can be tracked through mobile phones and communications can be intercepted... lone individuals or small groups can avoid the need for communication and their small numbers preclude infiltration."
He's also realistic about just how much we can really expect from the security services. "I'm not sure much can be done about this," he told me. "Counter-terrorism is always a form of triage, since in democratic societies there are not unlimited resources available to carry out round-the-clock surveillance on all potential suspects. There's no clear pattern to understand why person A becomes an angry extremist but remains peaceful, while person B becomes an angry extremist who engages in violence. The only solution is to watch both and, undoubtedly, one solution is to increase resources for counter terrorism. But even then, inevitably, someone will slip through the net."
This could be taken as frightening and depressing. Or maybe we just need to realise that, long-term, the most effective way to prevent terrorist attacks has less to do with the security services, and as much to do with us demonstrating clearly and defiantly that they don't work – that the open society will always triumph over the closed. Next week, Charlie Hebdo will publish a million copies of its magazine. Buy them. Share and re-share and flood the internet with every image they print.
The hashtag #jesuischarlie is ringing out just about everywhere. As is #jesuisahmed, in tribute to the Muslim gendarme who fulfilled Evelyn Beatrice Hall's injunction, dying to defend the right of others to say things he may not necessarily have agreed with himself.
For once, these online cyphers actually mean something.
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