Preventing Lone Wolf Terrorism: some CT Approaches Addressed

Preventing Lone Wolf Terrorism: some CT Approaches Addressed

by Edwin Bakker and Beatrice de Graaf [1]



After a brief discussion of the epistemological and phenomenological difficulties associated with the concept of lone wolf terrorism, a number of possible counter-terrorist approaches are discussed. Lone operator terrorist acts should be considered ‘black swan’ occurrences that are almost impossible to categorize or systematize, let alone forecast. Thus, not the profile of the perpetrator, but the modus operandi offer clues for a better response to this particular threat. Furthermore, almost all lone operators do display a degree of commitment to, and identification with, extremist movements – providing leads for preventing new rounds of radicalization within this potential group of sympathizers or followers. With the apparent increase of Islamist lone wolf terrorism and fears for right-wing extremists wanting to follow the example of the Norwegian mass murderer A.B. Breivik, new questions need to be posed, addressing the role of virtual communities with which lone operators identify themselves.



After the cold-blooded murder of 77 people in Oslo and Utoya (Norway) on 22 July 2011, the threat of lone wolf terrorism has quickly moved (further) up on the agenda of counter terrorism officials. Two questions were raised in the aftermath of the horrible killings by Anders Breivik : (i) could it have been prevented? and (ii) how to discover new plots, possibly by individuals who want to answer Breivik’s explicit call to follow his example? Both questions are difficult to answer. The Norwegian authorities are investigating the first question, which has already resulted in the arrest of the owner of an online trading business who is suspected of supplying chemicals to the Norwegian killer. Finding satisfactory answers to the second question – is it possible to discover and prevent future cases – is even more difficult. ‘Probably not’ is perhaps the most frank and honest answer, but an unacceptable one at that. In this article, we address seven possible counter-terrorist approaches to the threat posed by lone wolf terrorism with an eye on reducing chances of deadly attacks like the one experienced in Norway. First, however, we have to define lone wolf terrorism.


Defining the Concept

The term ‘lone wolf’ was popularized in the late 1990s by white supremacists Tom Metzger and Alex Curtis as part of an encouragement to fellow racists to act alone for tactical security  reasons when committing violent crimes.[2] Other terms that have been used to describe similar or comparable forms of political violence include ‘leaderless resistance’[3], ‘individual terrorism’[4] and ‘freelance terrorism’[5].

In this article the definition proposed by Burton and Stewart in a STRATFOR essay functions as the point of departure. They define a lone wolf as “a person who acts on his or her own without orders from — or even connections to — an organization.”[6] They stress the difference with sleeper cells, arguing that sleepers are operatives who infiltrate the targeted society or organization and then remain dormant until a group or organization orders them to take action. In contrast, “A lone wolf is a stand alone operative who by his very nature is embedded in the targeted society and is capable of self-activation at any time.”[7]. However, by stressing the absence of connections with a broader network or organization, Burton and Stewart neglect the ideological connections individuals might have with other networks or organizations, either through personal contacts or inspirational content on the Internet.

We focus our attention in this article on the operational aspect of lone wolf terrorism. Even though some lone wolves have been linked to larger (underground) networks, such as Baruch Goldstein (who has been linked to Kach) and Timothy McVeigh (who has been linked to several right wing-groups), they decided, planned and performed their act on their own, rather than as having followed instructions from some hierarchical command structure.[8] In our view, a definition of lone wolf terrorism has to be extended to include individuals that are inspired by a certain group but who are not under the orders of any other person, group or network. They might be members of a network, but this network is not a hierarchical organization in the classical sense of the word.[9]


No Single Profile

Infamous examples in the United States, Israel and Europe include Baruch Goldstein, an American-born Israeli citizen who was responsible for the death of 29 Muslims praying in the Cave of the Patriarchs in Hebron; the Austrian Franz Fuchs who used letter bombs to kill  four persons and injure 15 more; US army major Nidal Malik Hassan who is accused of a mass shooting at Fort Hood where 13 people died and 30 others were wounded, and the American mathematician Theodore Kaczynski, also known as the ‘Unabomber’, who engaged in a mail bombing spree that killed three persons and wounded 23 others. In addition, there have been several assassinations of political leaders committed by lone wolves. Think of Yigal Amir, the assassin of Prime Minister of Israel Yitzhak Rabin, or Volkert van der Graaf who killed the Dutch politician Pim Fortuijn.

These individuals and their violent acts exemplify the variations in targeting and modus operandi within lone wolf terrorism, as well as the variety of political and ideological backgrounds of the perpetrators. Anarchist revolutionaries, religious zealots, environmental and animal rights extremists, white supremacists and jihadists all have engaged in lone wolf attacks. When it comes to religious backgrounds we also see a variety of motivations.  Among those who claim or justify their acts in the name of a religion are individuals of all faiths. Muslim lone wolves like Nidal Malik Hassan and Abdulhakim Mujahid Muhammad who opened fire on a US military recruiting office, as well as anti-Semitic/Christian-identity adherents like Buford Furrow who attacked a Jewish Community Center and Eric Rudolph, also known as the Olympic Park Bomber, who killed two people and injured at least 150 others. Lone wolf terrorism also includes radical Roman Catholics like James Kopp and radical Protestants like Scott Roeder who both killed a physician who performed abortions.

Obviously, there is no single profile for a lone wolf. Nonetheless, it is possible to distinguish between different categories of lone wolf terrorists based on their ideological or religious background. In addition to this distinction, there are a few common characteristics shared by many lone wolves. One of the problems for both counterterrorism practitioners and academics is the relatively low number of terrorists who act their own without orders from – or even connections to – an organization. According to a study by COT/TTSRL, a total number of 72 lone wolf terrorist incidents accounted for only 1.28 percent of the total number of terrorist incidents in the US, Germany, France, Spain, Italy, Canada and Australia.10] This statistical quantité négligable turns these incidents into the typical ‘black swan’ occurrences that are almost impossible to categorize or systematize, let alone preview.[11] However, the number of incidents linked to lone operator terrorists seems to be on the rise.


Encouraging Lone Wolf Terrorism

The increase in lone wolf terrorism in the United States in the last three decades can partly be explained by the adoption and dissemination of the lone wolf tactic by and amongst right wing extremists.[12] For example, in the late 1990s the white supremacists Tom Metzger and Alex Curtis explicitly encouraged fellow extremists to act alone when committing violent crimes. A few years earlier, white supremacist Louis Beam, a former Ku Klux Klan and Aryan Nations member, popularized the strategy of leaderless resistance.[13] He envisaged a scenario where ‘all individuals and groups operate independently of each other, and never report to a central headquarters or single leader for direction or instruction”.[14]

Also, in Islamist circles the idea of support for small-scale, loosely organized terrorist attacks can hardly be called new. In 2003, an article was published on the extremist Internet forum  Sada al Jihad (Echoes of Jihad), in which Osama bin Laden sympathizers were encouraged to take action without waiting for instructions.[15] In 2004, Abu Musab al-Suri (or: Mustafa Setmarian Nasar), a dual citizenship Spanish-Syrian who had been in the inner circle around Bin Laden but fell out with him after 9/11 due to differences on strategic issues, published a “Call for Worldwide Islamic Resistance,” on the Internet. In this sixteen hundred pages manuscript, al-Suri proposes a next stage of jihad, characterized by terrorism created by individuals or small autonomous groups, which he also labelled “leaderless resistance”. These individuals will wear down the enemy and prepare the ground for the far more ambitious aim of waging war on  “open fronts” - an outright struggle for territory [16]. In 2006, Al Qaeda leader Abu Jihad al-Masri followed suit with a call to arms, entitled "How to fight alone" circulated widely in jihadist networks.

The 1,518 page-long manifesto of Anders Breivik can also be regarded as a guide into the workings of lone operator terrorism. In one part of his manifesto, Breivik explains how to publish documents on the Internet and how to use social media for recruiting purposes. Moreover, he shows the tricks he himself used to circumvent European custom agents and  describes in detail how he manufactured the explosives he used to blow up the government building in Oslo. Breivik also points at the possibilities of the use of unconventional weapons, such as Radiological Dispersal Devices, or so-called dirty bombs.


The Challenge of Fighting Lone Wolf Terrorism

Attacks by lone operator terrorists provide the most puzzling and unpredictable form of terrorism. Lone wolf terrorists are a nightmare for the counterterrorism organizations, police and intelligence communities as they are extremely difficult to stop.

First of all, lone wolves are solitary actors, whose intentions are hard to discern since they usually avoid contact with others. This makes identifying, monitoring, and arresting a lone wolf extremely difficult. Compared to (conventional forms of) group terrorism or network-sponsored terrorists, lone operators have a critical advantage in avoiding identification and detection before and after their attacks since most of them do not communicate their plans with other people. When militants operate in a cell consisting of more than one person, chances increase substantially that law enforcement authorities will be able to foil a terrorist plot. Breivik was well aware of this. He even warns other potential terrorists they will increase their chance of being apprehended by 100% for every other person they involve in their plans: “Don’t trust anyone unless you absolutely need to (which should never be the case). Do absolutely everything by yourself”, he writes in his manifesto.[17]

Second, even if lone wolves like Breivik make references to existing political or ideological discourses, they remain very hard to pinpoint as political terrorists/activists. This pose some problems to CT practitioners since insights into the disenfranchised, alienated or frustrated movement behind individual terrorists often provides clues as to their modus operandi, target preferences or outreach and/or propaganda activities. Lone wolfs, by definition, are idiosyncratic. They display a variety of backgrounds with a wide spectrum of ideologies and motivations: from Islamists to right wing extremists, and from confused suicidal psychopaths to dedicated and mentally healthy persons. This vast array of expressions and visions, ranging from ideological ramblings on the Internet and hate mail to fully-fledged acts of terrorism, hardly gives away anything in the sense of patterns or recurring methods behind lone wolf’s attacks.

Third, it is particularly difficult to differentiate between those lone operator extremists who intend to commit attacks and those who simply express radical beliefs or issue hollow threats (hoaxes). In Western countries in general and in the United States in particular, the freedom of speech is a fundamental freedom which limits possibilities to investigate radical scenes unless they  are violent.  While most terrorists are radical but not all radicals are terrorists, it is extremely difficult to single out lone wolves who will carry out an actual attack before they strike, even with the help of the most sophisticated technical intelligence gathering tools.

Fourth, lone wolves inspire copycat behavior and become role models for other alienated youngsters; they often invite bandwagon attacks. Kazcynski’s manifesto still circulates on the Internet, as do Bouyeri’s letters. And it is likely that we will see the same of Breivik’s ‘European Declaration of Independence’ ten to twenty years from now. In addition to this, certain tactics – shooting sprees, bomb letters, arson attacks or anthrax letters – also have a tendency to continue over a long period of time – although not necessarily by the same perpetrator.

Finally, although lone operator terrorists have the disadvantage of lacking the means, skills, and ‘professional’ support of terrorist groups or networks, their attacks nonetheless have proven to be very lethal — Anders Breivik and Timothy McVeigh are cases in point.


Possible CT Responses

How to deal with the threat of lone wolf terrorism and the challenge of identifying, targeting, and arresting persons who act entirely on their own? The question has not yet been sufficiently answered and poses the problem of how to reconcile fundamental principles of open societies with guaranteeing security to citizens. One thing, however, is clear: the challenge is enormous, especially when confronted with a person like Anders Breivik who used years to meticulously prepare his horrible attacks – the Oslo bombing (8 killed) and the Utoya massacre (69 killed).

Nonetheless, the above described commonalities and challenges provide some clues as to where to start with CT responses.

First of all, according to Alex Shone of the Henry Jackson society, a British-based think-tank, the key factor of the UK’s CT response concerning locating lone wolf attacks is in knowing not who will carry out an attack (almost an impossibility) but rather in knowing how such attacks are formulated. In his essay, Shone stresses the need to learn about the radicalization processes of lone wolves. He shows that insight into these processes open up possible avenues for effective CT measures to prevent or counter the threat of lone wolf terrorism.[18]

Knowing how lone operator attacks are formulated requires a far more sensitive detection system at the tactical, sharp-end of operations than most CT organizations currently use. According to Shone, CT services need to be far more attuned to those signals, as minimal as they might be, that any individual with a terrorist intent will inevitably give off in preparing his attack. This requires not only effective data capture and exploitation enabled by efficient overall information management, but also fused intelligence products. This requires intelligence analysts and collectors to work in far closer union.[19]

Secondly, given the ‘commonality’ shared by many lone wolves that there is a degree of commitment to, and identification with, extremist movements and that their radicalization process does not take place in a vacuum, it is important to both investigate and cooperate with afflicted communities. And given the general agreement that an effective counter radicalization strategy depends on effective community engagement, it is essential to promote passive and active aversion towards the terrorist seed in these communities with the help of influential community members.

In the third place, even a seemingly spontaneous combustion of violence is often triggered by some catalyst event. It could be rewarding to study and compare the nature of potential triggers or catalyst events in the radicalization processes of lone wolves. Are they located within the private domain or are they provided by outside political developments? Or are triggers even mastered by ‘entrepreneurs of violence’ who use them to call upon their anonymous followers to become active?

In the fourth place, exactly because lone wolves – although operating alone – draw inspiration from other extremists or ideologues, disseminating counter narratives ought to be an important element of an effective CT strategy. A crucial ingredient of counter narratives is  the de-legitimisation of perpetrators and their acts and the falsification of their ideologies.

In the fifth place, although lone wolves are not part of hierarchical organisations, they do formulate their acts in a certain context. Awareness programs for parents, schools, universities are worth considering – obviously without launching large-scale public campaigns that only serve to create a moral panic.

A sixth clue as to where to start with CT responses also involves communication processes. On the one hand, communicating the potential threat of lone wolves to relevant target audiences is very important. At the same it is important to refrain from handing them the public theatre they strive for. Handling lone wolves without giving them any positive public status should be one core principle. Of course, much depends on the channels used by the perpetrator. In the days of Kaczynski, one could, at least for a while, successfully prevent the publishing of his manifesto. Today, the Breivik case in Norway has shown that a lone wolf can send an email to possible supporters and post his video and the 1,500 pages of his manifesto on the Internet in the last remaining hour before he detonates the explosives and heads for his destination to engage in mass murder.

Lastly, perhaps the most concrete clue concerning lone wolf operators and their tactics is their modus operandi. In recent cases of shooting sprees (including high school shootings and mall shootings) all perpetrators were male and all had a license to possess (semi-automatic) firearms. This specific group of people who are allowed to keep firearms – of which the overwhelming majority are law-abiding citizens who use their weapon for hunting or sport shooting – needs special scrutiny. The same holds for the procedures for applying for a weapon permit and membership of a shooting club.


Final Remarks

As stated above, the challenge to prevent lone wolf terrorism is enormous and any CT response can only partly reduce this particular threat or limit its impact. As with other forms of terrorism, it is not possible to reach 100% security against this threat. Obviously, there is still a long way to go in preventing lone wolf terrorism. Potential answers on the ‘how?’ question regarding the modus operandi of lone wolf terrorists and their radicalization processes are still preliminary, needing further investigation. And with the apparent increase of Islamist lone wolf terrorism and fears for right-wing extremists wanting to follow the example of Breivik, new questions need to be posed, for instance about the role of the Internet or the possible impact of attacks on minority groups in society. The fact that there are – fortunately – few cases we can learn from does not make the task to know more about the ‘how’ of lone wolf terrorism any easier. Therefore, sharing experiences, data and ideas regarding this particular terrorist threat between practitioners, policy makers and researchers is essential to be able to develop at least some viable responses to lone wolf terrorism.


About the Authors:

Edwin Bakker is professor of (counter-) terrorism studies of the Institute of Public Administration of Leiden University where he teaches courses on terrorism and crisis communication. He heads the Centre of Terrorism (CTC) and Counterterrorism and is a Fellow of the International Centre for Counter-Terrorism (ICCT), both based in The Hague, The Netherlands. His research interests include violent radicalization, jihadist terrorism, including lone wolf operations and unconventional forms of terrorism and the potential threat of CBRN terrorism. Recently published work includes chapters in Rik Coolsaet (Ed.), Jihadi Terrorism and the Radicalisation Challenge, Ashgate, 2011 and in Gelijn Molier (Ed.), Terrorism, Ideology, Law and Policy, Republic of Letters, 2011.

Beatrice de Graaf is Associate Professor at the Centre for Terrorism and Counterterrorism/Leiden University and Fellow of the International Centre for Counter Terrorism, The Hague. Historian by training, she conducts research projects on ‘The making of the national security state, 1945-present’, ‘Terrorists on Trial’, ‘The global 1970s’ and ‘Female Terrorism’, focusing on Western countries. She published widely on topics addressing conflict and security issues in historical perspective. Her latest monograph is ‘Evaluating Counterterrorism Performance’ (Routledge, 2011).



[1]This article is based on a ICCT article on lone wolf terrorism by the same authors; it is available at With profound thanks to Liesbeth van der Heide for her research assistance.

[2] COT/TTSRL, Lone-Wolf Terrorism, Transnational Terrorism Security and the Rule of Law, July 2007. Cf:, p. 13.

[3] Jeffrey Kaplan. ‘Leaderless Resistance’, Terrorism and Political Violence, vol. 9 (1997), no. 3, pp. 80-95.

[4] Ze’ev Iviansky. ‘Individual Terror: Concept and Typology’, Journal of Contemporary History, vol.

12, no. 1 (January 1977), p. 45.

[5] H. W. Kushner. Encyclopedia of Terrorism, Thousand Oaks: Sage 2003, pp.  144-145; C. Hewitt.  Understanding Terrorism in America. From the Klan to al Qaeda, London and New York: Routledge 2003, p. 79.

[6] Scott Stewart and Fred Burton, ‘The Lone Wolf Disconnect’, 30 January 2008, Stratfor, Cf:

[7] Ibid.

[8] L. van der Heide. ‘Individual Terrorism: Indicators of Lone Operators’, 30 August 2011,  p.24.

[9] Marc Sageman, Understanding Terror Networks, Philadelphia: University of  Pennsylvania Press, 2004.

[10] COT/TTSRL, 2007, op. cit., pp. 16-17.

[11] N. N. Taleb. Fooled by Randomness: The Hidden Role of Chance in Life and in the Markets. New York: Random House, 2005.

[12] Mark S. Hamm, In Bad Company. America’s Terrorist Underground, Northeastern University Press, 2002.

[13] Louis Beam. ‘Leaderless Resistance’, The Seditionist, Issue 12, 1992, cf:

[14] COT/TTSRL, 2007, op. cit. p. 13.

[15] Integrated Threat Assessment Center (Canada), “Lone-Wolf Attacks: A Developing Islamist Extremist Strategy?”, 29 June 2007,

cf:, p. 4.

[16] Lawrence Wright, ‘The Master Plan’, in: The New Yorker, 11 September 2006, cf:; cf. ´Major Al Qaeda Leader Arrested in Pakistan´, on Foxnews, 2 May 2006.

[17] Andrew Berwick, 2083 – A European Declaration of Independence, London, 2011, p. 844.

[18] Alex Shone, ‘Countering lone wolf terrorism: sustaining the CONTEST vision’, Henry Jackson Society, 17th May 2010, Cf. .

[19] Ibid.


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