davesloggettSecurity Correspondent Dr Dave Sloggett looks at the issues arising from the attack at this week's Boston Marathon:

The carnage on the streets of Boston serves to remind us all that terrorism in an enduring threat to society. Whilst the three people that died and over 170 that were injured, many with life changing wounds, are tragic in their own right it could have been so much worse.

The bomber, whoever they were, seemed to have gone for a relatively primitive device that was small and contained in a pressure cooker. The design for such a device is readily available on the Internet. The ball bearings and nails were added to the device to increase its impact. Had it been made of higher grade explosives the death toll and imagery would have been even more dramatic.

Lone wolf attack 
Given the simplicity of the devices it is possible to speculate, with some confidence, that this is the work of a single individual or lone wolf. For the security services across the world this is the worst form of attack as the individuals involved can stay off the intelligence radar screen. The first time their plans are noticed is when they attack.

In the immediate aftermath of the event the inevitable focus turned to three main questions who are the perpetrators, why did they do it and how did they manage to pull off such an attack? As often with such events the latter question is often the one that can be answered first. The device is typical of devices built and used by Al Qaeda inspired terrorists.  

Jumping to conclusions
Given this single fact it would be tempting to draw a conclusion that this was an attack conducted by Muslim extremists. This is a course of action that President Obama was right to resist. In his first statement on the attack he made it clear that people should not “jump to conclusions”.

The problem with the events in Boston is that many of the indicators are contradictory. The near-simultaneous detonations of two devices a matter of seconds apart is a hallmark of Al Qaeda inspired terrorism. In London, Madrid, Baghdad and Pakistan this is a tactic that is frequently used to try and overwhelm the response of the emergency services.

Given these facts alone it might be tempting to think the attack had some link to Al Qaeda inspired terrorism. But these two facts are counter-balanced by another possible answer. That this event was not conducted by Islamic extremists but by ultra-conservative right wing Americans.

The attack was only a matter of days away from the anniversary of the bombing of the FBI building in Oklahoma. That occurred on the second anniversary of the end of the Wacko siege. It was also Patriots Day in Boston and coincided with Tax Day on which Americans are supposed to have filed their tax returns. This combination of dates could have been used by members of the extreme right wing in America as an excuse to carry out an attack full of symbolism.

Concealing bombs from prying eyes
However the extreme right wing is not noted for conducting indiscriminate attacks against American citizens. The Oklahoma attack targeted the FBI. It would be a significant departure for the extreme right wing from its past tactics. It may also provide an explanation as to why the bombs were relatively small in size. However the use of ball bearings and nails enhanced the human injuries that would inevitably occur. This suggests that the attacker(s) may have chosen to make the bombs smaller quite deliberately to conceal them from prying eyes.

The far right in America does have a track record of using explosive devices. The bomb used by Timothy McVeigh in Oklahoma was massive and required a van to be placed outside the target building. That killed 168 people and injured hundreds more. The Norwegian killer Anders Breivik also resorted to a large bomb in the initial attack on government offices in Oslo prior to going on his shooting spree which claimed the lives of 69 people, mostly teenagers, on the Island of Utøya. Clearly the attacker(s) is Boston would not have been easily able to park a vehicle loaded with explosives near the finish line. The attacker(s) had to resort to guile to ensure the devices were not discovered.

Working out a motive
In trying to work out the motive for the attack in Boston one thing appears to have escaped many of the commentators who rushed to contact the media to offer their so-called “expert” analysis of the attack. Why did the bombs go off when over 75% of those participating in the marathon had already passed the finishing line? This was nearly six hours after the start of the race.

Whilst the perpetrators may have wished to avoid an attack upon the elite runners, who are often drawn from quite an international base, if they sought to create maximum casualties why did they not attack when the main peak of runners was passing across the finishing line around four to four and a half hours after the start? Why leave it for just over another hour when those finishing may not have had such a level of support in the audience stands that were the subject of the attack?

This may suggest that the attacker(s) may not have wished to create large numbers of casualties and simply wanted to send a message. The relatively low yield of the devices also backs up such reasoning. It also provides additional weight to the argument that this was conducted by a lone individual. However whether they were inspired by extreme right wing rhetoric or the ideology of Al Qaeda remains unclear.

Past history of Al Qaeda attacks
Past history with Al Qaeda inspired terrorism shows that such reluctance to claim an attack is rare. Indeed the Pakistani Taliban, one group that has stated its intent to attack the mainland of the United States has been quick to put out a message denying involvement.

With Al Qaeda’s leadership fragmented by drone attacks in Pakistan it is just possible that it might take time for the so-called core leaders to realise this has been done in their name and hence are awaiting confirmation before making any statement. In contrast a lone individual affiliated to the extreme right wing may not wish to make any statement about their involvement. Preferring to retain anonymity and possibly conduct a follow-up attack.

Complex jigsaw puzzle
All of which leads to an inevitable conclusion at present. The evidence is does not immediately point to a specific group or individual. The serial numbers from the pressure cooker may provide a clue. Fingerprints or DNA on the fragments of the devices that have been retrieved may also help if the bomber was careless.

One thing however is abundantly clear. Over the coming weeks it is likely that many in the American law enforcement and intelligence services will be burning the midnight oil looking to piece together what at the moment is a complex jigsaw puzzle.