Abstract: This analysis of 47 cases of jihadist-inspired violence carried out in Western countries between January 1, 2012, and the June 12, 2016, Orlando attack sheds light on the evolving terrorist threat. The data shows that the Syrian civil war and the rise of the Islamic State have coincided with an increase in the number of attacks, with more than half of all violent incidents taking place in France and the United States. Notwithstanding the recent attacks in Paris and Brussels, most attacks were carried out by individuals with no direct ties to overseas terrorist groups and were low-tech and relatively ineffectual. Half of all attackers had a criminal past, and perhaps as many were unemployed. A majority of attacks targeted civilians, although violence was also frequently directed against members of law enforcement or the military. Knife attacks were the most common while shootings were the deadliest.
Shortly after 2:00 AM on the morning of June 12, 2016, Omar Mateen, an American citizen of Afghan descent, stormed into a gay nightclub in Orlando, Florida, and opened fire with an assault rifle and semiautomatic handgun, killing 49 people. Although many questions remain, Mateen pledged allegiance to the Islamic State in a 911 call made during the attack. This would make it the deadliest terrorist attack in the United States since 9/11 in addition to the deadliest mass shooting regardless of motivation. It thus appears to be the latest in a steadily growing number of jihadist-inspired violent incidents in Western countries. Some of these incidents, most notably the deadly, coordinated assault in Paris last November and the bombing in Brussels four months later, are clearly directed and funded by foreign terrorist organizations (FTOs). Others are carried out independently by autonomous groups and individuals who are often lacking substantial overseas connections but nevertheless share the same murderous ideology, while others still are conducted by troubled individuals who seem to be driven at least as much by mental illness as by exposure to jihadi propaganda or related media coverage.
Precisely where Mateen falls on this spectrum has yet to be established. The manifestation of jihadist-inspired violence in the West is clearly extremely diverse. It also appears to have increased substantially since the outbreak of war in Syria and the rise of the Islamic State. However, in order to gain a deeper understanding of the nature of the threat, it is important to examine the use of violence more thoroughly. This article analyzes all jihadist-inspired violent attacks executed in Western Europe, North America, and Australia from 2012 to the June 12 Orlando attack (i.e. since the escalation of conflict in Syria and Iraq). The analysis begins with a statistical assessment of the frequency and location of attacks, characteristics of perpetrators—including their links to foreign terrorist organizations (FTOs)—and modus operandi, followed by an examination of what the data reveals about the threat trajectory in the West.
Frequency of Attacks
From January 2012 to June 12, 2016, there have been 47 violent attacks in Western countries that were at least partially inspired by Islamist political concerns and/or violent jihadist propaganda and ideas, as promoted by al-Qa`ida and the Islamic State and widely covered in the media.[a] This compares to just 26 attacks during the entire preceding 11-year period, representing a significant increase in frequency. Moreover, the number of attacks has increased each year, with three in 2012, five in 2013, 11 in 2014, 16 in 2015, and 12 so far in 2016 (compared to five this time last year), which suggests a continuing upward trend in the coming months (see Figure 1).
Figure 1: Frequency of jihadist-inspired violent attacks in the West: January 1, 2012-June 12, 2016
Of the total 47 jihadist-inspired attacks since 2012, 11 (24 percent) were classified as “borderline,” meaning the jihadist component was present to varying extents but was far from clear, was often downplayed by the authorities, and was frequently overshadowed by mental health issues or bizarre circumstances. Examples include the beheading of a woman in Oklahoma in September 2014, an apparently Islamic State-inspired murder in Denmark the following month, the Lindt café siege in Sydney in December of the same year, and a fatal stabbing at Grafing train station, just outside of Munich, in May 2016. Arguably, such borderline cases should be excluded from the analysis; however, by including them—without necessarily labeling them acts of terrorism—one can gain a more complete understanding of the ways in which jihadist ideas are currently shaping, if not driving the expression of violence in contemporary Western society.
Location of Attacks
Since 2012 just eight Western countries have suffered attacks (see Figure 2). In rank order, these are France (17), the United States (10), Germany (five), Denmark and Australia (four each), Canada (three), and the United Kingdom and Belgium (two each). While attacks elsewhere in the West are certainly possible, if not probable, more than 50 percent of attacks so far have occurred in either France or the United States, suggesting that these two countries are particularly likely to experience jihadist-inspired violence in the near future.
Figure 2: Location of jihadist-inspired violence in the West: January 1, 2012-June 12, 2016
When examining who has been responsible for jihadist-inspired acts of violence in Western countries, it is immediately obvious that the overwhelming majority has been young males. There were 67 male offenders in total, with an average age of 25.9 (n=59), compared to just three females, with an average age of 19.7.[b] At least 23 percent of attackers (and perhaps 50 percent or more) were unemployed at the time they committed their offense(s); at least 50 percent had criminal records (all males); at least 20 percent of individuals were Islamic converts; and at least 14 percent had a documented history of psychological problems[c] (again, all males).
Although only one of the females committed an offense by herself,[d] the vast majority (70 percent) of all attackers acted alone, while another 19 percent acted in pairs, regardless of any extremist or terrorist affiliations. Just seven cases (15 percent) are presently confirmed to have had established links to FTOs, namely Mohamed Merah, Mehdi Nemmouche, and the Kouachi brothers (all linked to al-Qa`ida), and Ayoub el-Khazzani, the Paris and Brussels attackers, and Safia S. (each linked to the Islamic State). At least another two cases involved online communication with Islamic State members abroad;[e] however, for the most part the perpetrators of jihadist-inspired violence in the West have been lacking direct organizational connections or support. Notably, the average number of fatalities for FTO-linked attacks was 26.4, compared to just one for autonomous groups and lone actors.[f]
In terms of targeting, civilians have borne the brunt of jihadist-inspired violence in the West, much as they do elsewhere, having been targeted in 28 of the 47 cases included in this analysis (i.e. 60 percent; see Figure 3). Moreover, seven attacks against civilians were directed specifically against Jews and six of these took place in France, suggesting that anti-Semitism is particularly strong among French jihadis. Police were attacked in 16 cases (34 percent), although there were not always the primary target, while military personnel were attacked in 10 (21 percent). Different target-types were present in just seven cases (15 percent).
Figure 3: Targets of jihadist-inspired violence in the West: January 1, 2012-June 12, 2016
As shown in Figure 4, 21 cases (45 percent) have involved the use of edged weapons (knives and in one instance an ax), making them the weapon of choice among violent jihadists and their imitators in Western countries. A further 18 cases (38 percent) have involved the use of firearms, and these have accounted for the vast majority of casualties. Meanwhile, improvised explosive devices (IEDs) were used in just seven cases, resulting in fatalities in just three (Boston in 2013, Paris in 2015, and Brussels in 2016). Other forms of “weaponry” have included motor vehicles (used in four cases), bare hands (used twice), and boiling water (used just once, in combination with a razor blade). In six cases, not mutually exclusive of those mentioned above, multiple types of weapons were used in combination.
Figure 4: Weapons used in jihadist-inspired violent attacks in the West: January 1, 2012-June 12, 2016 (*Miscellaneous refers to bare hands/boiling water.)
What the Data Shows
Although it is important to bear in mind that the analysis here does not take the wider universe of prevented plots into consideration, it nevertheless provides important insights into the attacks that are most likely to take place. The fact that jihadist-inspired violence has increased substantially since 2012 demonstrates that the radicalizing influence of the conflict in Syria and Iraq, and of the Islamic State in particular, has not been limited to the mobilization of foreign fighters. However, it is important to note that the distribution of executed attacks does not appear to be proportionate to the scale of mobilization of foreign fighters in each country.
For instance, according to official estimates compiled by the Soufan Group, the United Kingdom ranks second in the mobilization of foreign fighters from Western countries, surpassed only by France, and yet has experienced the lowest number of attacks. Similarly, countries such as Sweden and Austria (jointly ranked fourth in number of foreign fighters) have not experienced jihadist-inspired violence after 2012.[g] Of course, given the degree of radicalization and foreign fighter flows, we might expect France to rate highly in terms of domestic attacks; however, to see the United States, which has produced a relatively small number of foreign fighters, in second place is rather more unexpected.
The causes of this variation are likely complex. France and the United States are both high-priority targets for violent jihadis for a variety of reasons, not least of which is their lead roles in the fight against the Islamic State, which raises the likelihood of attacks. The relatively high number of incidents in the United States may also be explained in part by the availability of firearms in combination with a relative lack of domestic facilitation networks in the country and the difficulty in reaching Syria and Iraq, leading to radicalized individuals launching attacks at home instead. Simply put, fewer opportunities to travel overseas to fight may result in greater incentive to act at home. This becomes especially relevant in light of the recent reduction in the rate of mobilization of foreign fighters, including a significant drop-off in the United States. Of course, the relative capability and resources of domestic security services also come into play, and yet it is impossible to prevent every attack, especially when faced with the threat of seemingly spontaneous acts of violence by lone extremists.
When it comes to the perpetrators of jihadist-inspired violence, it is quite remarkable to find such high rates of criminality, unemployment, and mental health problems in addition to such a high percentage of Islamic converts. Recent descriptions of Australian and European foreign fighters in particular have tended to emphasize socioeconomic marginalization. However, the percentages here are still surprisingly high when compared to earlier studies based on larger samples. There are at least two possible dynamics at play that are worthy of further exploration. One is that the socioeconomic status of Western jihadis in general has declined in recent years.[h] This would be consistent with generational trends described by Marc Sageman as well as current intelligence and law enforcement assessments. For example, in the United Kingdom, recent research by police and intelligence analysts revealed that “approximately 40 percent of the several thousand Islamist extremists across the country were committing low-level criminality with offenses that included benefit fraud, disqualified driving, and even drug crimes.” Indeed, as the director of Europol, Rob Wainwright, recently remarked, “the link between terrorism and crime is much more prevalent now than at any other time in the past.”
The other possibility is that there is a qualitative difference between the average Western jihadi and those who actually conduct domestic acts of violence. To some extent, this is a reflection of sampling bias. By focusing only on those attacks that were actually executed, there is a disproportionate number of lone actors (since they are harder to detect in advance) who are especially likely to be suffering from psychological problems. Similarly, the inclusion of “borderline” cases of jihadist-inspired violence, which have become more common in recent years, accounts for six out of 10 individuals with a documented history of mental health issues. It is also possible that the high rates of criminality in the current sample are reflective of greater skill and experience among criminals at evading the attention of law enforcement. Still, the perpetrators of jihadist-inspired attacks are still frequently disadvantaged compared to society as a whole. The apparent exception to this is females, who—although there were only three—did not have histories of criminality or mental disorder. The data here is thus suggestive of a mismatch between male and female jihadist offenders, the latter being younger and less obviously marginalized. Whether or not this holds true for Western jihadis in general and whether it is indicative of different motivations and/or processes of radicalization will require further research.
With respect to modus operandi, the observed preference for attacking civilians or unsuspecting uniformed personnel using knives or firearms is again partially related to the predominance of lone actors and the inclusion of borderline cases, both of whom are generally lacking in capability and are therefore more likely to attack soft targets using readily available weapons. What is significant, however, is how these variables have changed over time. Compared to the 26 incidents of jihadist-inspired violence in Western countries from 2001–2011, there is now clearly a stronger preference toward targeting police and using weapons other than explosives. The former trend may be due to a combination of contagion (i.e. copycat attacks) and the fact that police are likely to come into contact with criminals and people suffering from mental health problems, who together account for a significant portion of violent jihadist attackers.
As already noted, the latter trend (i.e. away from explosives) is related to the skills and capabilities of lone actors, but it is also a reflection of the willingness of FTOs to encourage and to sponsor directly more rudimentary forms of attack rather than accepting greater risk of detection in the hope of pulling off something more spectacular. Indeed, Islamic State spokesman Abu Muhammad al-Adnani spelled this out in excruciating detail in September 2014 when he declared to his followers that “if you are not able to find an IED or a bullet, then single out the disbelieving American, Frenchman, or any of their allies. Smash his head with a rock, or slaughter him with a knife, or run him over with your car, or throw him down from a high place, or choke him, or poison him.” These sentiments clearly resonate with a significant number of likeminded people and are continually echoed throughout jihadist circles. As one individual recently commented on the dark-web forum Shumukh al-Islam, “A simple operation killing two or three disbelievers and getting martyred in it… is better than a failed operation that didn’t even happen because you were captured.” Of course, the Islamic State’s commitment to attacking the West, combined with the return of significant numbers of foreign fighters—some of whom, like Brussels attacker Najim Lachraaoui, will have undoubtedly trained in explosives—suggests that we may yet witness a resurgence in the successful use of IEDs. Then again, this does not negate the increased chances of detection nor the fact that it is lone actors and small, independent groups that are consistently responsible for the majority of jihadist-inspired violence in the West. Whether or not he received any external support, Mateen’s actions are a reminder that individual attackers can achieve mass casualties. The majority, however, do not.
Amidst the current climate of fear and uncertainty largely centered around the Islamic State, there is a need for objective, empirically grounded analysis of jihadist-inspired violence. Although there is little doubt that the threat to the West has never before been greater, this reveals relatively little about what to expect. By examining the occurrence of jihadist-inspired violence as opposed to thwarted plots, which are often rather more ambitious, one gains a deeper appreciation of what is most likely to actually take place. On the one hand, the frequency of attacks has certainly increased. On the other hand, despite recent events, lethality has not. The average number of people killed in Western countries during the period 2001–2011 (excluding 9/11) was 10.1, compared to six from 2012–2016.
The fact remains that despite the Islamic State’s best efforts so far, the most likely attack scenario still involves lone actors (a significant number of whom appear to be driven as much by mental illness as by jihadist ideology) or small autonomous groups, using readily available weapons to attack soft targets and yet still generally resulting in failure. Granted, the situation is extremely dynamic and the tragic events in Orlando underscore the fact that terrorists do sometimes succeed in dramatic fashion. It is also quite possible that others will be inspired by Mateen and seek to replicate his actions elsewhere. Yet this does not change the overall balance of probabilities. The majority of jihadist-inspired violence in the West remains low-tech and, overall, relatively small-scale.
Sam Mullins is a professor of counterterrorism at the George C. Marshall European Center for Security Studies, Germany, and an Honorary Principal Fellow at the University of Wollongong, Australia.
Appendix: List of attacks included in the analysis
Cases marked with an asterisk are “borderline,” meaning questions remain about the motives involved.
March (France): Toulouse/Montauban shootings (7 dead)
September (France): Grenade attack on Jewish supermarket, Paris
December (Germany): Attempted bombing of Bonn train station
February (Denmark): Attempted murder of Lars Hedegaard*
April (United States): Boston marathon bombing and murder of police officer (4 dead)
May (France): Stabbing of a gendarme, Rousillon, Isère*
May (United Kingdom): Murder of a British soldier, Woolwich, London (1 dead)
May (France): Stabbing of a soldier, Paris
April–June (United States): Three shootings in Washington and New Jersey (4 dead)
May (Belgium): Shooting at Jewish Museum, Brussels (4 dead)
September (Australia): Stabbing of two police officers, Melbourne
September (United States): Beheading, Moore, Oklahoma (1 dead)*
October (Canada): Two Canadian soldiers run over, Quebec (1 dead).
October (Canada): Shooting at Parliament Hill, Ottawa (1 dead).
October (United States): Ax attack on NYPD officers, New York
October (Denmark): Islamic-State-inspired murder, Kvissel (1 dead)*
December (Australia): Lindt café siege, Sydney (2 dead)*
December (France): Attempted stabbing of police officers, Joue-les-Tours*
December (France): Car driven into pedestrians, Dijon*
January (France): Attempted strangling of a police officer, Metz*
January (France): Charlie Hebdo attacks, Paris (12 dead)
January (France): Shooting plus Jewish supermarket siege, Paris (5 dead)
February (Denmark): Copenhagen shootings (2 dead)
May (United States): Shooting attack, Garland, Texas
June (France): Beheading, St.-Quentin-Fallavier (1 dead)
July (United States): Chattanooga shootings (5 dead)
August (France): Attempted attack on Thalys train from Amsterdam to Paris
September (Germany): Stabbing of a policewoman by a convicted terrorist*
September (Denmark): Stabbing of a policeman, Sandholm asylum center*
October (Australia): Murder of a NSW police employee, Sydney (1 dead)
November (United States): Stabbing spree at University of California
November (France): Stabbing of a Jewish teacher, Marseille
November (France): Paris attacks (130 dead)
December (United States): San Bernardino shooting (14 dead)
December (United Kingdom): Leytonstone Tube stabbing, London
January (France): Car driven at French soldiers guarding a mosque, Valance
January (France): Attempted knife attack at Paris police station
January (United States): Attempted murder of a police officer, Philadelphia
January (France): Stabbing of a Jewish teacher, Marseille
February (Germany): Stabbing of a policeman, Hannover
March (Canada): Stabbing at a Canadian Forces recruitment center
March (Belgium): Bombing of Brussels airport and metro (32 dead)
April (Australia): Islamic State-inspired assault within prison, NSW
April (Germany): Bombing of a Sikh temple, Essen
May (Germany): Stabbing at Grafing train station, Munich (1 dead)*
May (France): Stabbing of a French soldier, Saint Julien du Puy
June (United States): Nightclub massacre, Orlando (49 dead)
[a] This data was collected using open sources. Note that in five cases, two or three acts of violence were separated by at least a day, giving a total of 54 actual attacks. These include the attacks by Mohamed Merah, the Tsarnaevs, Ali Muhammad Brown, the Kouachis, and Amedy Coulibaly. In addition, some attacks (such as in Paris and Brussels) involved multiple acts of violence within a short space of time. These are all counted as single cases for the purposes of this analysis. See appendix for full list of cases.
[b] This includes only confirmed, direct perpetrators of violence and therefore excludes any wider support networks.
[c] The possibility of mental health issues was raised in another 7 percent of male offenders in the sample.
[d] Safia S. stabbed a German police officer in the neck in Hannover in an attempted “martyrdom operation.” “German Prosecutors: Teen who Stabbed Cop ‘Supported IS,’” Deutsche Welle, April 15, 2016.
[e] These include the Garland, Texas, attackers of May 2015 and Yassin Salhi, who beheaded his boss in France the following month. Fran Blandy, “French Prosecutor Confirms ‘Terror Motive’, IS Link to Beheading,” Yahoo News, June 30, 2015; Rukmini Callimachi, “Clues on Twitter Show Ties Between Texas Gunman and ISIS Network,” New York Times, May 11, 2015.
[f] This calculation excludes the Orlando attack, given that information regarding possible links to FTOs has yet to be confirmed. If indeed Mateen received support from the Islamic State (or any other FTO), this would raise the average number of fatalities in FTO-linked cases to 29.3. If it transpires that Mateen acted autonomously, this would raise the average number of people killed in these cases to 2.4.
[g] In June 2015 a man of Bosnian origin drove a car into pedestrians before exiting the vehicle and attacking people with a knife in the Austrian city of Graz. However, authorities were quick to discount the possibility of terrorism and have not released any information that would indicate jihadist motivation. See “Police Reconstruct Events of Graz Tragedy,” The Local, June 23, 2015.
[h] Only three of 26 jihadist-inspired violent attacks from 2001–2011 were “borderline” cases.
 Evan Perez, Shimon Prokupecz, Catherine E. Shoichet, and Amy La Porte, “Omar Mateen Pledged Allegiance to ISIS, Official Says,” CNN, June 13, 2016.
 Joanna Jolly, “Alton Nolen: A Jihadist Beheading in Oklahoma?” BBC News, September 29, 2014.
 “Danish Teen who Killed Mum ‘Inspired by Isis,’” The Local, September 17, 2015.
 Louise Hall, “Lindt Siege Inquest Hears Man Monis Was a Mentally Ill Man who Became a Terrorist,” Sydney Morning Herald, April 7, 2016.
 “Bayern: Angreifer von Grafing Hatte Offenbar Psychische Probleme,” Der Spiegel, May 10, 2016.
 “Islamic State ‘Linked to France Factory Beheading,’” BBC News, June 30, 2015; Rory Mulholland, “Man shouting “God is Great” Tries to Strangle French Police Officer,” Telegraph, January 3, 2015.
 “Bourhan Hraichie in Court Accused of Carving IS Symbol on Cell Mate’s Head,” Sydney Morning Herald, May 26, 2016.
 “Foreign Fighters: An Updated Assessment of the Flow of Foreign Fighters into Syria and Iraq,” Soufan Group, December 2015.
 “Flow of Foreign Fighters to Iraq and Syria Reduced by Over 70% Says US-Led Coalition,” Middle East Monitor, May 18, 2016; Pete Williams, “FBI Director Comey: ISIS Is Losing Its Appeal in America,” NBC News, May 11, 2016.
 Simon Benson, “Aussie Jihadists were on the Dole,” Daily Telegraph, February 21, 2015; Robin Emmott, “Belgium’s Marginalized Muslims Fight in Syria ‘Out of Despair,’” Reuters, January 15, 2015; “Germany’s Jihadists: Young, Male, Losers,” The Local, September 11, 2014; Magnus Ranstorp, Linus Gustafsson, and Peder Hyllengren, “From the Welfare State to the Caliphate,” Foreign Policy, February 21, 2015.
 Edwin Bakker, Jihadi Terrorists in Europe: Their Characteristics and the Circumstances in Which They Joined the Jihad: An Exploratory Study (The Hague, Netherlands: Clingendael Institute, 2006); Sam Mullins, ‘Home-Grown’ Jihad: Understanding Islamist Terrorism in the US and UK (London, United Kingdom: Imperial College Press, 2016); Marc Sageman, Leaderless Jihad: Terror Networks in the Twenty-First Century (Philadelphia, Pennsylvania: University of Pennsylvania Press, 2008); Marc Sageman, Understanding Terror Networks (Philadelphia, Pennsylvania: University of Pennsylvania Press, 2004).
 Sageman, Leaderless Jihad, pp. 48–50, 125–146.
 Richard Walton, “Protecting Euro 2016 and the Rio Olympics: Lessons Learned from London 2012,” CTC Sentinel 9:6 (2016): pp. 1-6.
 Vivienne Walt, “Europe’s Top Cop: It’s ‘Almost Certain’ Terrorists Will Try to Strike Again,” Time, May 16, 2016.
 Paul Gill, John Horgan, and Paige Deckert, “Bombing Alone: Tracing the Motivations and Antecedent Behaviors of Lone-Actor Terrorists,” Journal of Forensic Sciences 59:2 (2013): pp. 425–435; Clark McCauley, Sophia Moskalenko, and Benjamin Van Son, “Characteristics of Lone-Wolf Violent Offenders: A Comparison of Assassins and School Attackers,” Perspectives on Terrorism 7:1 (2013).
 “IS Spokesman Rallies Fighters Against U.S.-Led Coalition, Threatens Enemy and Calls Individual Muslims to Launch Attacks,” SITE Intelligence Group, September 21, 2014.
 “Jihadist Advises Lone-Wolf Fighters in Tunisia, Urges to Act and Not Wait for Instructions from Leaders,” SITE Intelligence Group, May 13, 2016.