Policy Memos

The Boston Bombings: A Post-Qaeda Take on “Lone Wolves” and “Leaderless Jihad”

Policy Memo:


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Any immediate or early comments on major terrorist attacks, such as the April 2013 Boston marathon bombings, are bound to be highly speculative. They may actually add to the general confusion rather than help dispel it. At times, they may even become part of the very political mayhem that is one of the main intended outcomes of a terrorist attack.

There are some aspects, however, that can be seriously analyzed at any stage, such as the political effects of an attack domestically and internationally; in relation to the Boston bombings, for example, one can follow the stream of impacts on U.S.-Russia bilateral relations. Another aspect that can be examined is to place an attack in the context of other acts—in the Boston case, where it stands in relation to other homegrown jihadist terrorist acts committed by single actors  or cells in the West, particularly in the United States where such incidents have displayed a clear spike over the past 3-4 years. To what extent do the Boston bombings fit into the broader trends of jihadist terrorism in the West? Do they conform to the so-called “leaderless resistance” paradigm? How do they fit into the more general patterns of single actor attacks in the United States? This memo concludes that the attack by the Tsarnaev brothers is likely to be categorized not as a “lone wolf”-type incident but as an act by a solo cell that behaved on its own initiative even though it had some external connections.

“Leaderless Resistance” and “Global Jihad”

The recent rise in single actor/single cell attacks, especially in the West, and especially of the radical Islamist type, has been driven by several factors. One of these is the structural shift and adaptation of the global jihadist movement itself to changing circumstances. The cutting edge of strategic and organizational thinking for this movement is best summarized by Abu Musab as-Suri’s theory of “jihad by individual cells” (the movement is better known in the West as “leaderless jihad,” a term coined by Marc Sageman in his book under the same title).

The Boston marathon bombings are commonly described as a case of either “leaderless resistance” or ”lone wolf” terrorism (or both). While these two concepts are at times used interchangeably, they generally differ in regards to the main type of actor. “Leaderless resistance” mainly refers to terrorism as a network strategy and organizational pattern consciously adopted, often under pressure, by loose networks of cells and individuals to strengthen asymmetrical advantages vis-à-vis hierarchically-structured opponents. “Lone wolf” terrorism implies attacks by stand-alone individuals or cells acting independently from any group or network. It is not surprising that the two phenomena are often confused in cases such as the Boston bombings. This is partly due to a lack of information about a cell’s links in the early stages of an investigation, but it is also due to the particular difficulties of establishing the nature and connections of someone who acts outside a formal organizational framework and lacks traditional leads associated with the latter. In part, this confusion results from a genuine overlap between “leaderless resistance” and “lone wolf” terrorism, especially in the global jihadist movement.

While today “leaderless resistance” is commonly associated with the global jihadist movement, the concept was originally developed by the extreme right in the late 1980s and early 1990s. What its godfather, U.S. white supremacist Louis Beam, had in mind were very flat networks, with a complete absence of top-down authority.[1] “Leaderless resistance” was defined as a matter of conscious organizational choice in favor of a strategy that “allows for and encourages individuals or small cells to engage in acts of political violence entirely independent of any hierarchy of leadership…”[2] While Beam’s original concept encompassed “lone wolf” attacks by stand-alone individuals (and applies to high-profile acts of right-wing terrorism, such as the Oklahoma City and the Atlanta bombings in the United States in the mid-1990s, as well as the 2011 Oslo attacks), his main hopes were vested in a multiple-cell leaderless structure—hopes that never materialized for the far right.

The concept of a multiple-cell leaderless movement has been more successfully applied by radical environmentalists, notably the Earth Liberation Front (ELF). With no centralized organization, leadership, or membership roll, ELF violence has been less deadly than mass-casualty attacks by stand-alone right-wing terrorists, but the network emphasizes sabotage, resulting in heavy property damage, and has achieved a high frequency of attacks (100 per year on average in the late 1990s and early 2000s). The concept is also sometimes applied retrospectively to anarchists as a highly decentralized movement built upon semi-autonomous cells and voluntary associations. While acts of anarchist terrorism (including high-profile political assassinations in the past) often resulted from spontaneous individual actions with the help of a few friends, “leaderless resistance” should only be projected onto that movement with care; for anarchists the “leaderless” impulse was not inherently linked to violence in the first place but reflected their general strategic, organizational, and ideological preferences.

At present, “leaderless resistance” is primarily applied to the al-Qaeda-generated “global jihad.” While some disagree with this usage completely, others, including this author, disagree only in part, claiming that not all that is understood or meant as global jihad fits the pattern of “leaderless resistance.” While the movement is a complex structure and more an exception than the rule in several ways, it combines some of the key network features with select pre-network and post-network elements and is the most well-known transnational terrorist network. In contrast to locally-based groups who either combine nationalism with religious extremism or are driven by nationalist aspirations (and thus are likely to mirror more hierarchical structures of nation-states), this supranational movement is guided by a universalist religious ideology that in principle does not favor strict hierarchies (unlike totalitarian cults). To what extent, and to which layer of global jihad, is “leaderless resistance” applicable depends on how one understands the movement and its evolution in organizational terms. For brevity’s sake, let us confine ourselves to two main approaches.

The regionalization approach has prevailed in mainstream U.S. and Western discourses since the late 2000s. It disaggregates “global jihad” into three levels. First, it leaves some direct strategic command role for “al-Qaeda Central” centered in Pakistan and Afghanistan but acknowledges its declining role. Second, it argues that the movement’s center of gravity has shifted toward several organizationally coherent regional affiliates in Muslim regions—to “al-Qaedas” in the Arabian Peninsula, Iraq, the lands of the Islamic Maghreb, East Africa, and Southeast Asia. The third level is formed by al-Qaeda’s “ideological adherents”—small cells and individuals who “know the group only through its ideology to carry out violence in its name.”[3] The rise of such homegrown cells is interpreted as a sign of either the movement’s capacity to adapt to changing circumstances or of al-Qaeda’s organizational degradation (resulting primarily from counterterrorist pressure by the United States and its allies).

The post-Qaeda approach denies residual strategic command function for the al-Qaeda core beyond a symbolic and/or ideological role. It questions the role of regional affiliates as al-Qaeda’s main successors and centers of gravity, arguing that most of them have strong homegrown roots and promote agendas inextricably tied to respective regional or local conflicts, while their pledges of loyalty to al-Qaeda are more nominal than substantive. Instead, a looser network of smaller cells, active in over 70 countries and promoting an explicitly globalist agenda, is seen as the cutting edge and the main driving force of global jihad. In contrast to groups tied to specific local and regional contexts in the Middle East, Asia, or Africa, this type of cell is truly “extraterritorial” in outlook and goals, with most of them emerging in Western rather than Muslim states. These cells display diverse radicalization paths and are not linked to one another in any formal way, but they share the ideology of global jihad and together form—and see themselves as part of—an adaptive and resilient transnational network-type movement. Despite its marginality, this movement can still pose a serious terrorist threat to international security.

Whichever of the two approaches one follows, it is the micro-cell level to which elements of “leaderless resistance” apply. The movement does not recruit into a pre-existing framework but encourages people to start their own cells to further its ends; there is little or no intra-movement communication between cells; the idea of starting a violent cell appeals as much to young males’ desire for glory and their personal conscience as to their political or ideological beliefs. This list of characteristics is actually a description of the ELF (see Joosse 2007), but it equally applies to the micro-cell level of global jihad, if not to the movement’s dispersed ideological and strategic leaders nor its regional affiliates.

“Lone Wolves” and “Global Jihad” 

While “leaderless resistance” originates from an organization-centered perspective, “lone wolves” act outside organizational frameworks.

On the one hand, “lone wolf” terrorism remains a relatively marginal phenomenon. The absolute majority of terrorist attacks are carried out by organized groups. The number of incidents plotted or carried out by “lone wolves” is miniscule: they make up less than 1.8 percent of terrorist attacks in Western states between 1968–2010. Single actors display less destructive capacity, sustainability, and longevity. With the exception of several mass-casualty attacks, acts of “lone wolf” terrorism are less deadly: they have an average lethality of 0.6 deaths per incident, a statistic that has not appeared to increase over time.

On the other hand, “lone-wolf” jihadist terrorism in the West shows some marked specifics. Islamist terrorists, who only became a significant issue from the 1980s and early 1990s, already account for 15 percent of the total number of single-actor attacks in the West over the past 40 years, second only to right-wing extremists with 17 percent.[4] “Lone wolf” attacks also account for a much higher proportion of global jihad incidents, compared to other types of terrorist incidents: 14 percent of all plots and attacks by jihadist actors in Western Europe between 1995 and 2012.[5] Single-actor jihadist incidents aim at more casualties, as half of all plots involve mass casualty bombings. Also, while throughout the 2000s a gradual increase in “lone wolf” terrorist incidents mostly affected Western Europe, in the late 2000s and early 2010s, jihadist plots and attacks of this type also increased in the United States. Out of 40 such attacks committed or prevented in the United States between 2001 and 2011, over half occurred between 2009–2010. In 2010, CIA director Leon Panetta described “lone-wolf” terrorism as the main terrorist threat to the United States.

There are enough cases of “lone wolf” attacks to give rise to typologies of single actor terrorism, jihadist or otherwise (see, for example, works by Petter Nesser and Raffaello Pantucci). The main distinction usually made is that between pure “lone wolves” and so-called solo terrorists. “Lone wolves” act entirely on their own—for example, the Fort Hood shooting in 2009 by Maj. Nidal M. Hasan, the stabbing in 2010 of a British MP by Roshonara Choudhry, and the plots by Khalid Aldawsari in 2011 to bomb former U.S. president George W. Bush’s Dallas home as well as the homes of former Abu Ghraib guards. In contrast, “solo terrorists” have some operational, financing, training, or other network ties and connections. They are, in turn, divided into those who still act on their own initiative (Abdulhakim Muhammad, who was responsible for the 2009 shooting at a recruitment office in Little Rock, Arkansas), and those who act in close cooperation with a broader network (Uma Faruk Abdulmutallab, who tried to bring down a Detroit-bound jetliner with a suicide bomb in 2009, and Faisal Shahzad, who in 2010 planted a car bomb in New York City’s Times Square). In practice, however, it is not always easy or possible to make a distinction between “lone wolves” and “solo actors,” especially at earlier stages of an investigation.

While the recent trend in jihadist terrorism in the West points to some increase in “lone wolf” attacks, as compared to attacks by single actors (cells) with some network connections, this has ambiguous implications. The good news is that purely “lone” operations demand a lot in terms of skills and abilities, usually producing a mismatch between qualification and ambition that usually results in failure. The bad news is that tracking down “lone wolf” terrorists is particularly problematic, as these individuals or cells are generally not in contact with similar actors or organized groups, do not necessarily get external training, and often acquire their weapons and materials independently and from open sources. Even more problematic is that few single actor terrorists are real “loners.” Despite a recent spike in “lone wolf” incidents, the dominant type of jihadist terrorism in the West remains solo terrorism, with at least some connections beyond virtual ones. Often, even what at first seems to be a “lone wolf” tends to reveal a more complex pattern of “network agent” terrorism, as the cell’s various connections are gradually unraveled—a good example here is the “Leeds cell,” which was responsible for the 2005 London bombings. Or, following a broader typology of “homegrown terrorism” in the West, what at first appears as an internal-autonomous actor often turns out to be an example of internal-affiliated terrorism.

The Boston Cell

One of the main criteria for single actor typologies in terrorism are the external connections of a mini-cell or one-man cell. When there is a shortage of connections, any links become crucial. The chief suspects in the Boston Marathon attacks—the Tsarnaev brothers—might or might not have acted as an integrated part of a larger network, but they are certainly part of a larger phenomenon, particularly in the United States. However, the exact type of the Boston cell can only be finally established after the facts, nature, and scale of its connections are clarified.

At first, the Tsarnaev suspects were commonly referred to as a “lone wolf” cell. The surviving brother claims they acted alone. The FBI cautiously confirmed that the evidence points to “homegrown violent extremists” acting “in retribution for the wars the United States waged in Iraq and Afghanistan.” Other similarities with previous post-9/11 attacks of this type abound. The cell was formed by young, U.S.-based, and relatively integrated first generation migrants of unexceptional social background. The older brother held a green card, while the younger was a naturalized U.S. citizen since 2012. No direct connections to known extremist groups were found by the CIA or the FBI, who had looked into the matter upon a lead from the Russian government. Nor was there anything new in having a suspect that had been or was under investigation by U.S. security agencies end up plotting and committing a terrorist attack—there have been at least four such cases in the United States since 9/11. The suspects were hardly well-versed Islamists in the religious sense, but one or both of them were clearly inspired by the global jihadist abhorrence of U.S. actions in the Muslim world, specifically in Iraq and Afghanistan. Domestic radicalizing influences and connections in the United States, such as a potential radicalizing influence from one or more individuals and/or by previous jihadist terrorism cases, need to be further explored. The Tsarnaev cell was not the first case in which Cambridge mosque-goers faced terrorism charges in the United States or abroad. While it remains to be seen how the suspects acquired weapons, explosives, and funding, one of them bought fireworks from the same Phantom Fireworks company that sold fireworks to Times Square plotter Faisal Shahzad. 

Against these similarities, there are two distinct characteristics specific to the Boston cell that do not exactly fit the pattern of previous single actor jihadist terrorism in the United States.

First, the heavier-than-usual damage caused by the attack is atypical for single actor jihadist terrorist acts in the West. The Boston attack killed three people on the spot and injured over 260—an unprecedented number of casualties for a post-9/11 jihadist attack on U.S. soil. Some previous post-9/11 plots in the United States involved larger volumes of explosives but were not successful. While half of all plots of these type in the West involve plans to cause mass casualties, very few lead to actual mass-casualty attacks. In fact, there were only three such previous cases after 2001: the 2004 Madrid bombings, the 2005 London bombings, and the 2009 Fort Hood shooting (the fourth most lethal terrorist attack in contemporary U.S. history). In all three cases, some degree of specialized expertise or professional connections was in place. This record, coupled with some indications of a higher degree of sophistication in the Boston explosive devices than what one can get from Internet manuals, suggest the presence of some specialized training or qualification in the Tsarnaevs’ case, even despite some possible elements of spontaneity (after the Boston attacks, the brothers were reported to have impulsively contemplated another bombing at Times Square).

Second, all previous single actor jihadist incidents in the United States have involved some link to either Iraq and Afghanistan-Pakistan as theaters of U.S. direct military and security involvement (or, to use jihadist terminology, “open fronts” of “liberation wars”) or at least to areas where U.S. covert involvement has taken place (such as Yemen). These links went beyond general inspiration or declared justification for an attack: they involved either suspects of Afghan or Pakistani-American origin, including those who sought some direct training in these countries, or those, like Hasan, with first-hand experience of the wars in Iraq and Afghanistan. For such U.S.-based jihadists, the United States forms an obvious end-target.

In the case of the Tsarnaev brothers, due to their ethnicity, country of origin, and the older brother’s six-month trip to the North Caucasus in the first half of 2012, the main external (foreign) source of the cell’s links explored by the U.S. government was the Russian Caucasus and, more specifically, potential connections to the “underground” in Dagestan where the United States has not had direct or covert security involvement. So far, investigators found no operational or other substantive link between the Tsarnaevs to organized militant groups in the North Caucasus, despite the older brother’s trip to the region. In Dagestan itself, it is a rare case when an official account by the republic’s Ministry of Internal Affairs coincides with that of the underground “Command of the Mujahideen of the Caucasus Emirate’s Dagestan Province,” but both deny that the Tsarnaevs had any contact with the local “underground,” with the rebels even stressing that the “Mujahedeen in the Caucasus are at war with Russia not the United States.” This is not surprising, as even in the context of the post-9/11 war on terrorism, the U.S. policy on conflict and terrorism in the North Caucasus can by no means be described as one favoring pro-government authorities there. But some connections between the Tsarnaevs to the radical environment may exist. Take, for example, William Plotnikov, a Canadian ex-boxer turned Islamist radical; after his arrest in Dagestan in 2010 it was found that he had discussed jihad over e-mail with the older Tsarnaev, allegedly prompting Russia’s first alert/info request to the United States. However, one problem with such connections is that Plotnikov and other alleged contacts of the Tsarnaevs appear to have been killed back in 2012. In fact, connections of this type—a few foreign contacts and visits to conflict-torn regions for ideological inspiration, sometimes also in hope to get some training, are quite common for most homegrown jihadists in the West today, with one critical nuance: these are normally connections/trips to internationalized jihadist “open fronts” (Afghanistan/Pakistan, Iraq, Yemen, and Somalia). Leading strategic thinkers of global jihad, such as Anwar al-Awlaki or Abu Musab as-Suri, also normally distinguish “open fronts” and extraterritorial individual-type jihadists based in the West from local/regional insurgencies aimed against central governments, such as the conflict in the North Caucasus. Nor are the Islamist militants in the North Caucasus usually mentioned by leading Western experts on global jihad as a regional affiliate of the movement (such as al-Qaeda in the Arabian Peninsula or in the Islamic Maghreb).

Links to regions other than the main open theaters or areas of U.S. direct or indirect security involvement are not entirely inconceivable for U.S.-based cells, but they are extremely rare (like the bizarre plot by ethnic Albanians, Palestinians, and a Turkish man against Fort Dix in New Jersey in 2007). Also, while jihadists’ links to the North Caucasus are highly untypical for attacks in the United States, there have been several precedents in Western Europe when individuals from the North Caucasus were involved in jihadist plots in the name of an explicitly transnational agenda. In 2010, for example, a Chechen-Belgian ex-boxer, Lors Dukaev, injured himself while preparing a letter bomb to be sent to the Danish newspaper Jyllands-Posten to avenge the caricatures they published about the Prophet Muhammad. Another example are suspects of North Caucasian origin who were among those arrested in relation to terrorist plots in Spain in August 2012 against British and U.S. targets and in France in February 2013 against targets in Spain. For the most part, however, terrorist cells from the region have focused on Russia, and the 2013 Boston attack will not change this basic reality. 


The Boston attack needs to be placed in the broader context of single-actor jihadist terrorism in the West. While it is clear that the Boston Marathon bombing was not an al-Qaeda operation, once the type, scale, and limits of the Boston cell’s connections are better established, the suspects may well end up falling under the category of a network agent that engaged in a “jihad of individual terrorism,” a phrase used by global jihad strategists. Officially, the attack is likely to be eventually categorized not as a “lone wolf”-type incident but as an act perpetrated by a solo cell with some external (domestic and foreign) connections that acted on its own initiative. More broadly, it is likely to emerge as a case of internal affiliated terrorism, the dominant pattern of homegrown Islamist terrorism in the West. The attack, however, stands out for at least two less typical features that point in opposite directions and partly contradict each other. On the one hand, it is harder to identify the usual mismatch between qualifications and ambitions in the case of this rare successful mass-casualty attack by a jihadist single actor. This suggests some specialized professional training or outside support. On the other hand, purported links to the North Caucasus as a particular regional context are atypical for U.S.-based jihadist terrorists (of the past decade) who plot attacks on the U.S. homeland, even if such links have some precedence among jihadist cells in Europe. 

[1] Louis Beam,Leaderless Resistance,” The Seditionist, No. 12, 1992.

[2] Paul Joosse, “Leaderless Resistance and Ideological Inclusion: The Case of the Earth Liberation Front,” Terrorism and Political Violence 19 (2007): 351-368.

[3] “National Strategy for Counterterrorism” (Washington D.C.: The White House), June 2011.

[4] Ramón Spaaij, “Understanding Lone Wolf Terrorism: Global Patterns, Motivations and Prevention,” Springer Briefs in Criminology (Dordrecht; Heidelberg; London; New York: Springer), 2012. 

[5] Petter Nesser, “Single Actor Terrorism: Scope, Characteristics and Explanations,” Perspectives on Terrorism 6, no. 6 (2012).


About the author

Lead Researcher, Department of International Politics; Head, Peace and Conflict Studies
Institute of World Economy & International Relations (IMEMO), Moscow