Terrorist attacks planned and perpetrated by lone individuals have become an increasing problem over the last decade. Whilst large group-based terrorist organisations such as ISIS and Al-Qaeda will continue to pose a security threat, the US government, and its domestic intelligence agencies, will need to develop strategies to stifle the trend by which one or two lone-actors prepare and perform acts of terrorism. However, anticipating and preventing such attacks poses a significant challenge for counterterrorism officials, and one with no obvious solution.

Timothy McVeigh is often regarded as the United States' archetypal lone-actor terrorist. His murder of 168 people in the 1995 Oklahoma City Bombing demonstrates just how lethal an individual can be, if given enough time to organise and plot. Indeed, in comparison, the 2005 London bombings, carried out by four men with assistance from Al Qaeda, claimed 52 victims. However, McVeigh is actually an anomaly. Most instances of lone-actor terrorism in the United States claim very few, if any lives, and rarely exceed double figures. This is primarily because lone-actor terrorists often lack experience, formal training and, because they occasionally suffer from mental health problems (31%), are poor planners and executers. Lone-actor terrorism has become symptomatic of America's terrorism problem in the 21st century, and recent examples include; the 2006 Chapel Hill Ramming Attack, the 2009 Fort Hood Shootings, the 2013 Boston Marathon Bombings, and the 2014 New York Hatchett Attack.

A distinguishing feature of lone-actor terrorism is the departure from suicide bombings as a primary tactic towards the use of non-explosive weapons, such as guns, knives, motor vehicles, and even light aircraft. These non-explosive weapons, particularly vehicles and knives, are easy to procure without arousing suspicion, and as the FBI have stated, can be rendered lethal on an ad-hoc basis "with minimal prior training or experience". The problem is, that US intelligence agencies have developed strategies for locating and monitoring groups who might be preparing explosives, however, they are less apt at predicting whether someone is purchasing a gun, knife or vehicle for nefarious, rather than mundane, reasons. Simply put, this new strategy of terrorism is difficult to predict, and can occur rather more spontaneously, than more 'traditional' terrorist attacks, which require the cooperation of a large number of people operating within an organisation, and with an established ideology and strategy.

That is not to say that lone-actor terrorists lack an ideology. Lone-actors are often inspired by a particular extremist ideology. For example, James Von Brunn, who opened fire at the US Holocaust Museum in Washington D.C, in 2009, was inspired by right-wing nationalism and anti-Semitism. Similarly, lone-actors are often inspired by other terrorist organisations, such as ISIS, however, they are infrequently officially affiliated to one, and largely operate outside their command and control structures. It is this lack of formal affiliation which renders lone-actors more difficult to trace and monitor by intelligence agencies.

However, one location that intelligence agencies can draw their attention to is the internet, which acts as a primary source of motivation and technical knowledge for lone-actor terrorists, and according to Jamie Bartlett, head of the Violence and Extremism Program at Demos, "has both increased the possibilities and the likelihood of lone-wolf terrorism". The Internet has made it easier for extremist material to reach individual Americans who can be coaxed or coached into conducting their own attacks. The internet's centrality to lone-actor terrorism means that young people are particularly likely to become radicalised. This is confirmed by a survey carried out by Brain Jenkins at RAND who, after analysing instances of lone-actor terrorism in the United States between 2002-2009, found that the median age for lone-actors was 27. Thus, the internet will prove a key battleground for intelligence agencies to stem the rise of lone-actor terrorists.

One reason for the rise of lone-actor terrorism within America is because U.S. intelligence agencies have become more effective in anticipating the destructive actions of the larger and more established terrorist organisations. After all, the last major terrorist attack on American soil was September 11, over a decade ago. Operating as a large-scale terrorist organisation requires a greater flow of communications. The more communications exchanged, the more likely one's organisation will be intercepted and monitored. This probability also increases if terrorist organisations are communicating across state borders as Al-Qaeda and ISIS often do. However, what intelligence agencies are less proficient at, is intercepting and monitoring the private thoughts and plotting of individuals. Of course, these individuals are utilising the internet to seek inspiration and prepare, but anonymising internet servers such as TOR (which ironically was developed by the US Naval Research Laboratory in 2002), gives these individuals a degree of protection from intelligence agencies. Indeed, terrorist organisations such as Al-Qaeda and ISIS are aware of this development, and are encouraging individuals to further their cause by murdering western citizens in their own countries. Abu Mohammed al Adnani of ISIS, for example has urged the group's supporters, to "smash his head with a rock, or slaughter him with a knife, or run him over with your car". Similarly, a 2010 edition of Al Qaeda's Inspire magazine suggests that budding jihadists can attach sharp steel blades or butcher's knives to the front of a 4-by-4 pickup truck to create "a mowing machine, not to mow grass but mow down the enemies of Allah". Indeed, the Boston Bombers, Dzhokhar Tsarnaev and Tamerlan Tsarnaev learned to build explosive devices using pressure cookers from an online edition of Inspire.

Lone-actor terrorism is a decentralisation of the previous group-based model of terrorism. Despite being less lethal, the frequency and randomness of this D.I.Y. terrorism, renders it a terrifying phenomenon within the United States. But what are the potential strategies available to US intelligence agencies, which could alleviate this problem?

Is there a solution to the Lone-Actor problem?

The unpredictability and apparent spontaneity of lone-actor terrorism means that it would be foolish to assume that there is a universal remedy to this phenomenon. One difficultly lies in the fact that it is incredibly difficult to stop a lone-actor who has not yet committed a crime. Whilst intelligence agencies may be tempted to monitor every individual who encounters extremist material online, many of those looking at extremist material do not harbour extremist sympathies, but are rather researchers, or merely curious individuals. Moreover, monitoring everyone who finds extremist material online would require incredible resources and manpower to achieve. French intelligence services, for instance, are already finding it difficult to handle the terabytes of online data they have been granted permission to collect, in response to the recent Charlie Hebdo attacks. Furthermore, the National Security Agency (NSA) has struggled in light of the Edward Snowden leaks to provide evidence that its own mass surveillance of digital data has managed to prevent any instances of lone-actor terrorism. In addition, there are a variety of legal issues involved with US intelligence agencies monitoring US citizens. Although, the NSA have bypassed this issue, by arguing that because many internet communications leave the US border, that they can be considered as foreign communications.

US intelligence agencies are certainly interested in profiling lone-actors, in order to anticipate which individuals are worth targeting and monitoring. However, according to research into 119 lone-actor terrorists carried out by Paul Gill from University College London, there is unfortunately no set profile for lone-actor terrorists. For example, although, lone-actors tended to be young, they were not exclusively so, and the ages of lone-actors ranged between 15 and 65. Indeed, James Von Brunn, presumably overlooked by Gill's study, was 89 when he attacked the US Holocaust Museum. Similarly, the classic stereotype of lone-actors being socially isolated 'losers' no longer fits the bill. Gill found that many (53%), but not all, lone-actors were socially isolated. Whilst there was a tendency for lone-actors to be single (76%) and unemployed (40%), there were still a number of lone-actors who were happily married and in stable employment. Thus, whilst profiling lone-actors can provide some indication, as to which types of individual might become lone-actors, it is highly unlikely that US intelligence agencies will be able to develop a reliable rule of thumb. Inevitably, someone will slip through the net.

Of course, implementing mass-digital surveillance programmes may foil some lone-actor terrorists, but governments and their intelligence agencies may wish to ask whether this is worth curtailing the civil liberties of their population en masse, the majority of which will be law-abiding citizens, and also, whether extensive monitoring may disillusion and marginalise individuals in a manner which may encourage their radicalisation? After-all the NSA has already suffered massive reputational damage as a result of the Edward Snowden leaks, and this mistrust amongst the American people has spread into other government departments. Though instances of lone-actor terrorism are incredibly unfortunate, in comparison to other causes of death within America such as obesity, traffic accidents and ordinary homicide, lone-actor terrorism is a minor threat. As Andrew Coyne has suggested, perhaps what the US government, and their allies need is some perspective and stoicism. After all, he argues, that "we live with the reality that a certain number of murders will take place every year, or a certain number of traffic deaths. We can live with this."

If stoicism is a pessimistic and unreasonable course of action, perhaps limiting the access and lethality of the weapons favoured by lone-actors provides a better, albeit limited solution. For example, by implementing more rigorous gun control laws, and combating the illegal trafficking of weapons on the black market, perhaps less weapons, or at least, less deadly weapons will get into the hands of wannabe terrorists. Of course, given America's allegiance to the second amendment, implementing such regulation is easier said than done. Similarly, another plausible, though costly remedy, might be the erection of anti-ramming bollards to protect important buildings and busy pedestrian centres. Indeed it has been suggested that thebollards located outside Glasgow Airport significantly reduced the damage done from their 2007 ramming attack. Another, area for consideration, lies in the social-networks of lone-actors. Although, lone-actor terrorist attacks seem impulsive when they are perpetrated, they often require months of prior planning, as demonstrated by Gill's sample, where 29% of lone-actor terrorists engaged in dry runs. Often, lone-actors will share their plans, and seek legitimisation from other individuals, such as friends and family. In 64% of cases, the offender told their friends and family about their intentions, and in 58% of cases, other individuals knew about specific plot information. Thus, the friends and families of potential lone-actors can play a key preventative role. The US Government has often stressed the importance of everyday Americans in countering terrorism. To a certain extent, post 9/11, we have all become micro-vigilantes. Various information campaigns have trained us to report suspicious behaviour, and look out for anomalies in our environment, such as unattended luggage. However, Americans are largely unaware about how to recognise extremist traits amongst their family and peers, or the events (such as unemployment, or marital breakup) which may lead lone-actors to convert their catastrophic musings, into lethal actions. Spreading such information amongst the general public may prevent some lone-actor terrorists successfully instigating their plans, however, there will always be the issue of friends and family being unwilling to turn their loved-ones over to the authorities.

To summarise, the potential for lone-actors to wreak havoc within the United States remains an unfortunate reality that is unlikely to be eliminated any time in the near future. Trying to address this problem is certainly a worth-while task, but a task that we would be naïve to assume we will be successful at. Perhaps a change of attitude and perspective is needed after all. #News