Reassessing the Threat of Homegrown Violent Extremism in the United States: Overstated or Underestimated?

Taylor Applegate

Introduction

Every day, countless headlines stream across the news describing recent terrorist plots, attacks on civilians across the western world, and updates on the latest atrocities committed by the Islamic State in Syria and the Levant (ISIL). In particular, the past several years have born witness to a steep increase in ‘lone-wolf’ or lone offender attacks conducted by homegrown violent extremists (HVEs). Although the majority of these attacks have occurred primarily in Europe, Southeast Asia and the Middle East, widespread media coverage has generated significant concern within the United States. According to a recent poll, 86% of Americans are very concerned or somewhat concerned about “lone offender terrorist attacks in which individuals in this country decide to take terrorist action on their own” (Washington Post 2016).

However, the public’s risk-perception may reflect an exaggerated media emphasis, incongruous to the true degree of threat posed by HVE activity within the US. In the ten years following 9/11, there were only eight homegrown terrorist attacks motivated by Islamic jihadist goals, compared to a whopping eighteen inspired by right-wing extremist motives based on political, religious, or identity-based hatred (New America 2016). Nonetheless, the public’s concern is understandable given the rapid spread of ISIL and its role in generating a new wave of HVE attacks around the globe. In only two years since the violent regime first declared itself a worldwide caliphate, over 1,200 people have been killed in homegrown terrorist attacks (outside of Iraq/Syria) coordinated or inspired by ISIL (Yourish et al. 2016). The increase in these attacks spurs an incredibly prudent question: has the rise of ISIL increased the threat of self-radicalized homegrown terrorist attacks within the US, and in what form is an attack a) most likely and b) potentially most dangerous?

In order to calculate the risk of any particular threat, one must assess the likelihood of an attack being attempted by an adversary, based on the actor’s intent and capabilities (Risk Steering Committee 2010, 36). An accurate threat assessment will thus require determining the extent to which potential HVEs 1) possess strong motives to conduct a terrorist attack, and 2) have access to the necessary means to do so. Based on analysis of earlier attacks and current literature on the topic, I hypothesize that ISIL’s proficiency at spreading jihadist ideology to individuals with personal or political grievances, vulnerable to rapid self-radicalization, has increased the threat of lone offender style terrorist attacks by HVEs. Social media and technological developments have allowed ISIL to reach a much wider audience to which it offers purpose and belonging, while encouraging terrorist attacks through relatively simple methods.

Most research on the topic has focused on the motives behind these attacks and possible methods for improving law enforcement’s ability to prevent them. However, a deeper dive into the historical trends is needed to determine the extent to which ISIL’s rise has affected the likelihood and potential danger of lone-wolf terrorist attacks motivated by radical Islamic ideology. An accurate assessment of the current risk posed by HVEs within the US will facilitate consideration of policy measures aimed at reducing the long-term threat to homeland security.

Literature Review

An accurate analysis of the current research and literature discussing the relative HVE threat in the US first requires the establishment of common definitions. Most academic work applies the definition outlined in the DHS Lexicon, describing an HVE as “a person of any citizenship who has lived and/or operated primarily in the US or its territories who advocates, is engaged in, or is preparing to engage in ideologically-motivated terrorist activities (including providing support to terrorism), in furtherance of political or social objectives promoted by a foreign terrorist organization” (Office of I&A 2011). The critical distinction between an HVE compared to a traditional domestic terrorist is that the individual’s actions are motivated by a foreign terrorist organization and/or its ideology, even if he or she is not directly or officially associated with the group.

Applying this common definition, the next step in assessing the current threat environment requires an understanding of its historical origins and development. External and homegrown terrorist attacks were brought to the forefront of US homeland defense concerns following the September 11th hijackings. As the “Global War on Terror” ramped up, tightening security measures created new challenges for Al Qaeda’s efforts to conduct large-scale terrorist attacks in the style of 9/11. Ever adaptive, Al Qaeda thus began shifting its strategy towards recruiting foreign homegrown terrorists, encouraging citizens of Western nations “to implement a campaign of individual jihad and do-it-yourself terrorism” (Jenkins 2011, 7). Europe suffered the brunt of these initial HVE attacks; a total of 244 people were killed and more than 2,700 were injured amid homegrown terrorist bombings targeting public transportation in 2004 in Madrid and 2005 in London.

While these attacks spurred fear and concern about the HVE threat in countries around the globe, the US remained relatively immune. From September 11th, 2001 to the end of 2014, the US had only six jihad-inspired attacks, resulting in 25 deaths (New America 2016). Furthermore, a RAND study of homegrown terrorism in the US found that in the ten years between 2001 to 2011, of the 176 Americans indicted or arrested for involvement in 32 terrorist plots, only 10 had developed even a basic semblance of operational plans (Jenkins 2011, 8). Researchers have attributed the higher frequency and intensity of HVE attacks in Europe, relative to the US, to a number of factors including intelligence and law enforcement gaps, proximity to terrorist breeding-grounds, logistical accessibility, higher numbers of foreign terrorist fighters, and poor integration of the Muslim minority populations (Byman 2016). Most scholars agree that while Al Qaeda’s efforts up through 2011 were limited in number and scope due to a lack of both determined intent and competent capabilities, the rise of ISIL in mid-2014 has renewed the threat of more adept HVEs. There is currently a wide consensus among key policymakers that HVEs pose the greatest challenge to homeland defense. According to Department of Homeland Security (DHS) undersecretary for intelligence and analysis, Francis X. Taylor, lone offenders inspired by foreign radical ideologies “top the list of hazards” to homeland security (Ackerman 2016). The June 2016 Orlando nightclub shooting by Omar Mateen, motivated by self-proclaimed allegiance to ISIL, has reignited concerns about the risk of HVE and doubts as to where the US Intelligence Community (IC) and law enforcement agencies (LEAs) are doing enough to prevent these attacks.

When breaking down this threat, most of the literature focuses on the motivations that drive lone offenders towards violent extremist ideologies. The logic driving this research emphasis is that if ISIL is able to inspire more widespread radicalization, the IC and LEAs will face an uphill battle against growing numbers, resulting in more plots that go undetected (Brooks 2011, 11). The literature is split on this question because, while ISIL is certainly spreading its message to a wider audience, it remains difficult to even estimate how many individuals are becoming radicalized. Without any proof of increasing rates of radicalization, some experts argue that the HVE threat continues to be overstated. Just a year ago, The New York times published an article highlighting that since 9/11, “nearly twice as many people have been killed by white supremacists, anti-government fanatics and other non-Muslim extremists than by radical Muslims” (Shane 2015). However, in the year that followed, these statistics have shifted dramatically; D.C. based research center New America now tallies 94 people killed in “violent jihadist attacks” compared to 48 killed in attacks by lone offenders with far-right wing motives (New America 2016). Considering a single attack can entirely reframe the threat calculus, as occurred with the 49 people killed in the Orlando shooting, arguments that rely solely on comparative statistics of this nature hold little weight. Despite ongoing debate on whether HVE attacks pose a considerable threat to the US, academics agree that ISIL has managed to spread its ideology with greater ease than Al Qaeda and previous affiliates due to the introduction of social media and the internet. The few dozen terrorist websites in the early 1990s exploded to more than 4,000 sites by 2006, replacing print publications with online forums, encrypted emails and webzines that put “English-speaking, Internet-savvy jihadists” just “a mouse click away” from potential self-radicalizing HVEs (Bergen 2016). Fundamentalist Islamic organizations have used these new technologies to evolve "from a top-down enterprise masterminded by a few core groups to a decentralized system of recruitment and inspiration”, a strategy which CNN’s top national security analyst Peter Bergen refers to as “leaderless jihad” (Nagl 2016). Overall, as the internet and social media enhance ISIL’s ability to reach more potential recruits, the odds increase that susceptible individuals will self-radicalize and begin planning attacks with little to no actual direction from the group.

As ISIL uses technology to reach a wider audience, the question remains as to why certain individuals radicalize while the vast majority of Muslim communities remain moderate. Because each individual HVE will have slightly different cognitive pathways that lead from personal grievances to violent action, these theories are best applied as a foundation for systematic inquiry. Several theories provide greater insight into the motives that drive an individual to radicalize and turn to violent means of jihad, including Social Movement Theory (SMT) and Social Psychology Theory (SPT). The first of these emphasizes the need for a social movement to ensure its own survival and prosperity through four critical tasks: “Forming mobilization potential; forming and motivating recruitment networks; arousing motivation to participate; and removing barriers to participation” (Borum 2011, 17). In order to inspire membership and participation, ISIL uses a “narrative that touches on all facets of life -- from career opportunities to family life to a sense of community” (Steinbach 2016). Once an individual has joined the cause, SPT concepts of “group think” explain why ISIL is so effective at spurring radicalization. Terrorist organizations reduce individual agency and encourage extreme or polarized attitudes that “criticize certain social injustices, offenses, or threats that affect a terrorist's reference community” (De la Corte 2007). These groups highlight the supposed injustices against Muslims committed by so-called “western infidels”, creating a common enemy while emphasizing violence as the only effective method in gaining retribution.

In addition to ISIL’s heightened aptitude for inspiring self-radicalization, a second way in which the threat of HVE attacks could increase is an improvement in tactics, techniques and procedures (TTPs). Relatively simple weapons and tactics can substantially bolster lone offenders’ capabilities to cause greater destruction in a single attack. This is perhaps the most dangerous outcome, because any single plot that slips through the cracks has the potential to result in massive casualties. The 2013 bombings of the Boston Marathon by Tamerlan and Dzhokhar Tsarnaev is one example of the destructive power of relatively simple or homemade improvised explosive devices (IEDs), particularly when deployed in a high-density public space. The attack resulted in only three fatalities but 250 additional injuries, all due to two self-radicalized individuals who found purpose and belonging through online contacts with militant jihadists, and became convinced that retribution against the US for its policies in Iraq and Afghanistan would be their ticket into heaven (Gunaratna and Haynal 2013).

The current gap in the literature is the lack of updated assessments following the dramatic and rapid rise of ISIL beginning in 2014. However, the limited research and commentary on the impact of ISIL leans towards the assessment that the HVE threat will continue to persist, if not worsen, due to organization’s widespread campaigning on social media and the internet. Paired with easy access to the resources necessary for executing highly destructive TTPs, rising rates of radicalization could lead to an increase in both the frequency and magnitude of attacks. For this reason, this study will focus on analyzing cases in which ISIL has been able to tangibly inspire radicalization and encourage/inform enhanced capabilities among HVEs within the US.

Research Methodology

In the past two years, HVE attacks seem to be skyrocketing across the globe - a phenomenon that has largely been attributed to ISIL’s success in recruiting a growing number of lone offenders to self-radicalize and conduct attacks on their own volition. For that reason, this study will focus on terrorist attacks in which offenders’ motives for self-radicalizing were tied to ISIL, whether through claimed allegiance or other evidence of affiliation to the group. With the aim of filling research gap on the degree to which ISIL-inspired lone offenders pose a threat to the American homeland, the scope of the study will be limited to attacks conducted in the US.

In order to test my hypothesis that ISIL’s widespread dissemination of jihadist ideology will lead to increasingly frequent and more destructive HVE attacks, I will conduct a historical analysis of the five ISIL-inspired attacks occurring on American soil since the group first declared its caliphate in mid-2014. In each of these cases, I evaluate the 1) motives behind the attack, 2) the method of radicalization, and 3) the targets selected and the TTPs used for preparing and executing the attack. If past attackers are being recruited, trained and self-radicalizing through methods that are near impossible to catch, we can assess that the risk of a plot going undetected is high. Additionally, research into the TTPs used in each instance, as well as those generally encouraged by ISIL, will provide insight into the potential degree of destruction posed by a single successful attack. In order to assess whether each attack could have been prevented, I will analyze each case for any evidence of missed warnings and indicators that could have been detected by intelligence or law enforcement agencies (4). This portion will naturally help identify weakness and areas for future improvement in counterterrorism methods, allowing for a forward-looking policy recommendation. The four aforementioned qualitative variables will be supplemented by assessing quantitative data in two categories; roughly how long the individual took to radicalize and plan the attack (5), and the degree of damage inflicted (number of people killed and/or wounded) (6).

All of the data will be collected from deep-dive multi-source research into the five cases of ISIL-inspired attacks in the US, as compiled through analysis The New York Times (Yourish 2016). Although I will focus on law enforcement’s reporting of the circumstances leading up to each attack, the possibility of news media misreporting or skewing facts opens the door for potential bias. Using primary sources whenever possible and referencing multiple news outlets will help fact-check my data. The predominant limitation of the historical case study methodology is that threats are constantly changing and evolving. Every day, ISIL is working to develop techniques to enhance recruitment efforts while self-radicalized HVEs devise new TTPs to avoid detection and maximize casualties. Yet, while an adversary is far from guaranteed to behave the same way it has in the past, assessing previous TTPs is one of the best ways to establish a baseline for predicting future actions. Such an analysis will provide a forward-looking assessment of likelihood and potential ramifications of future ISIL-inspired attacks.

Analysis, Findings and Policy Implications

For each of the five ISIL-connected terrorist attacks that have occurred in the US, analysis of the motives, method of radicalization and the TTPs used suggests the threat of homegrown attacks will only continue to increase as ISIL’s social media messaging campaign reaches greater numbers of potential recruits. Motives across all five cases were quite similar on the surface level; a desire to cause symbolic destruction and death among non-believers in the name of jihad. Additionally, the attempted shooting in May 2015 at a Prophet Muhammad cartoon contest in Garland, Texas gives evidence of a secondary motive - the desire to garner attention and recognition from the extremist community. On the day of the planned attack, shooter Elton Simpson posted on Twitter "“Follow @_AbuHu55ain,” prompting users to refer to the Twitter account of Junaid Hussain, a British-born foreign fighter in Syria and one of ISIL's most infamous hackers. Just over an hour before the attack began at 7 p.m., Hussain eluded to imminent violence on that same account, posting “The knives have been sharpened, soon we will come to your streets with death and slaughter!” (Callimachi 2015). Experts assess that Simpson likely urged others to follow Mr. Hussain on Twitter in order to draw broader attention to his forthcoming attack; “He wanted to make sure everyone in those circles knew what he’d done,” reported Veryan Khan, who helps run the Terrorism Research and Analysis Consortium (Callimachi 2015).

Attention-seeking motives likely grow out of a potential attacker’s desire to obtain status within extremist networks that provide a sense of community and belonging to isolated individuals. One attacker, Zale Thompson, was described as “an out-of-work recluse, who spent hours in his room on the computer browsing radical websites and occasionally left comments on Facebook and YouTube that disparaged whites and Christians and most recently supported violent jihad" (Schwirtz and Rashbaum 2014). In each of the five attacks, individuals radicalized domestically over several years, although with varying degrees of integration and involvement in online jihadist networks. Due to its widespread publicity and high-volume messaging campaign, ISIL has been able to reach larger numbers, thus increasing the risk that individuals susceptible to radicalization will plot and carry out attacks. For example, as counterterrorism experts have pointed out, the Garland, Texas case displays how “the Islamic State and its supporters use social media to cheerlead for attacks” as evidenced by the gunman’s Twitter communications with ISIL promoters (Inserra 2014). In the remaining four cases, however, there is no evidence that ISIL had established contact with the attackers, nor directed, planned or assisted in the plot.

ISIL’s ability to plant the ideological seed and foster the growth of violent jihad without tangible assistance or direct communications poses an enormous challenge to intelligence and law enforcement efforts. Aside from the Garland, Texas case, all the attackers studied self-radicalized in relative isolation, meaning there were few if any warning signs and thus little that law enforcement can do to prevent an attack. Some experts have suggested screening Google searches and social media posts for certain keywords and internet “patterns of life” in order to detect potentially nefarious activity. While this tactic would be useful in developing watch lists, it could lead to substantial false positives and more importantly, directly conflicts with the indispensable American rights of free speech and privacy. Certainly, it is not a crime to express one's beliefs even if they support extreme Islamic ideals. With that said, any explicit threat or ultimatum issued online or via social media, related to Islamic extremism or otherwise, ought to be treated as a serious threat to public safety and handled through law enforcement action.

Take the following scenario from the attack in Garland, Texas: On April 23, ten days before the attempting shooting, an account under the name of Mujahid Miski (believed to be Mohamed Abdullahi Hassan, a top recruiter for ISIL) shared a link on Twitter to a listing for the Muhammad cartoon contest and goaded his followers to attack it: “The brothers from the Charlie Hebdo attack did their part. It’s time for brothers in the #US to do their part,” ...Among the nine people who retweeted his call to violence was gunman Mr. Simpson.” (Callimachi 2015). More effective methods for sifting through massive amounts of open source data and social media posts are needed in order to catch warnings and red flags evident in the weeks and days leading up to attacks. Flagged accounts could be tracked on digital watch lists monitoring open source online activity as well as attempts to purchase firearms, plane tickets, or other materials conducive to attacks. While each of these actions alone may prove circumstantial, when taken together the odds of a present threat increase dramatically.

Meanwhile, intelligence-driven policing could bring such capabilities to the tactical level to interdict attacks as new indicators emerge hours and minutes before violence. For example, minutes before arriving at the event in Garland, Simpson claimed an oath of allegiance to the leader of the Islamic State, Abu Bakr al-Baghdadi in his Tweet using the hashtag, “#texasattack: May Allah accept us as mujahedeen" (Callimachi 2015). Had Simpson been flagged after retweeting the explicit call-to-action targeting the cartoon contest, security teams in live communication with tactical intelligence operators could have been warned. If LEAs and the IC develop tools to take advantage of time-sensitive tippers and open source information, ISIL’s greatest tool could become its greatest weakness.

However, in some cases there are not sufficient warnings on social media or otherwise. The attackers responsible for the San Bernardino shootings on December 2, 2015 were by all means an average American family; Syed Farook worked at the local county health department (the target of the attack), while his wife, who had recently passed a national security background investigation to become a permanent resident in the US, stayed home with the couple’s six-month old daughter (Ahmed 2015). There were no clear indicators that the couple had extremist views, aside from later reporting that Malik had allegedly posted allegiance to ISIL on a Facebook account under an alias, and Mr. Farook had been in “touch via phone and social media with at least one person whom the FBI suspected of international terrorism” (Ahmed 2015). Two individuals quietly self-radicalized, without any evidence of direct ISIL collusion, leaving the IC or LEAs without any realistic means to detect or prevent the attack.

Overall, common trends among these five cases suggest the threat of ISIL-inspired HVE attacks will only continue to rise in frequency and perhaps magnitude as long as the organization is able to continue spreading its ideology. The threat environment will likely be characterized by attacks conducted by self-radicalized ISIL sympathizers, as opposed to operatives coordinating directly with ISIL leaders. Rather than targeting critical infrastructure, government or military facilities, the five recent cases suggest the most likely targets will be large gatherings, police officers, and/or groups that particularly offend Islamic ideology. Firearms were the weapon of choice in 80% of the cases examined: in two of the cases involving semi-automatic assault rifles, the San Bernardino and Orlando attacks, a total of 63 people were killed and another 70 injured by the shooters. This analysis creates a most likely scenario of one to two shooters bearing automatic rifles, targeting a large group gathering. However, more dangerous scenarios abound; regardless of regulations on firearms, highly-adept intelligence-led policing, or mass data collection and monitoring of social media, the increasing number of self-radicalizing individuals means a greater number of plotted attacks, leaving some bound to go undetected. With a plethora of destructive capabilities easily accessible, from firearms to homemade explosive devices, an effective preventative approach will require a strategic approach that addresses the root cause of homegrown violent extremism.

Conclusion

While some law enforcement and intelligence improvements could enhance the ability of preventing future terrorist attacks, the five cases examined in this study show that a long-term solution must be aimed at preventing self-radicalization in the first place. Reducing the attractiveness of ISIL’s extremist ideology will require a sweeping, multi-faceted counter-messaging campaign. The US and its partners in the counter-ISIL coalition must focus on targeting ISIL’s communication nodes both on the physical battlefields of Iraq and Syria as well as the virtual communes of cyberspace. This effort could be assisted by establishing and disseminating a common core narrative to emphasize 1) the coalition’s assistance and support to Muslim communities and 2) ISIL’s inadequate governance, poor defense and violent oppression of its people (Gambhir 2016). This narrative ought to be supplemented with aggressive efforts to defend against ISIL propaganda, including working with social media companies to block and remove accounts who promote violence.

Finally, doubling-down on efforts to encourage integration of Muslim immigrants into American communities, both respecting and welcoming diverse cultures, would go leaps and bounds in preventing homegrown extremism (Parker 2016). In particular, ensuring young Muslims have opportunities to find purpose and belonging in local American communities is critical in reducing the chances that they will turn to ISIL or other extremist organizations to meet these needs. Maximizing integration would not only undercut rates of radicalization, it would also assist law enforcement efforts to gain critical information from Muslim communities. Inclusion and civic engagement are the best means of ensuring all minority populations feel they can trust turning to law enforcement when in need. This, in turn, will strengthen police’s partnership with local religious communities and leaders who are absolutely critical to preventing radicalization before it can take root, and tipping off law enforcement when it does.

The rise of ISIL has substantially transformed the HVE threat environment by using social media and the internet to promulgate jihadist beliefs and encourage terrorist attacks from afar. Once these ideas are planted in the minds of vulnerable individuals who self-radicalize in quiet isolation, it can often be difficult for the IC or LEAs to detect and preempt violent plots. Because many cases are so challenging to detect, a better strategy towards securing the homeland and preventing future attacks should be directed at the ideological origins that motivate would-be HVEs. Such efforts will require a long-term dedication to maximizing social integration of Muslim communities at home, tailoring counter-messaging and targeting communications nodes abroad, and quelling the hatred and violence espoused on social media platforms in cyberspace. History has shown that following Al Qaeda and ISIL there may rise another yet-unheard of fundamentalist organization. Considering the enduring yet evolving nature of this threat, a comprehensive effort to undermine the messaging and motivation driving self-radicalized violent extremism will be the only approach sufficient in securing the American homeland for decades to come.

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