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The psychological effects of cyber terrorism

Michael L. Gross, Daphna Canetti & Dana R. Vashdi

To cite this article: Michael L. Gross, Daphna Canetti & Dana R. Vashdi (2016) Thepsychological effects of cyber terrorism, Bulletin of the Atomic Scientists, 72:5, 284-291, DOI:10.1080/00963402.2016.1216502

To link to this article: https://doi.org/10.1080/00963402.2016.1216502

Published online: 04 Aug 2016.

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The psychological effects of cyber terrorismMichael L. Gross , Daphna Canetti and Dana R. Vashdi

ABSTRACTWhen ordinary citizens think of cyber threats, most are probably worried about their passwordsand banking details, not a terrorist attack. The thought of a shooting in a mall or a bombing at anairport is probably more frightening than a cyber breach. Yet terrorists aim for mental as well asphysical destruction, and our research has found that, depending on who the attackers and thevictims are, the psychological effects of cyber threats can rival those of traditional terrorism.

KEYWORDSCyber security; cyberterrorism

Cyber aggression has become a daily fact of life in the21st century, yet for most people it’s still only a realityin the form of cyber crime – hackers targeting financialinformation or other personal details. Politically moti-vated attacks might threaten them as well, but theytend to be the concern of governments and corpora-tions rather than ordinary citizens. The thought of aterrorist shooting in a mall or bombing in an airportprobably seems far more frightening to the averageperson than Russian hackers disrupting governmentnetworks in Estonia or Anonymous breaking into thepolice department of Ferguson, Missouri. Cyber terror-ists, after all, have yet to actually kill or injure anyone.Yet our research has found this perception of cyberaggression might not be entirely accurate. The aim ofterrorism, after all, is not just physical destruction, anddepending on who the attackers and the victims are,the psychological effects of cyber terrorism can be justas powerful as the real thing.

Defining cyber terrorism

People face cyber aggression on an almost daily basis.Hackers appropriate, erase, or ransom data, defraudbank customers, steal identities, or plant malevolentviruses. In many cases, hackers are criminals out forpecuniary gain. But sometimes their motives are poli-tical. Some are “hacktivists,” or cyber activist groups,like Anonymous, others are terror groups like Hamasor Islamic State, and still others are agents of nationalstates like Iran, North Korea, or Russia. They are notusually after money but pursue a political agenda tofoment for social change, gain political concessions, orcripple an enemy. Sometimes their means are peaceful,but other times they are vicious and violent. The lines

often blur. Anonymous will hack the Ferguson policedepartment just as it will initiate an “electronicHolocaust” against Israel in support of the Palestiniancause (Rogers 2014). Islamic activists will use theInternet not only to recruit members and raise fundsfor social welfare projects but also to steal money forterrorist activities or disseminate information to stokefear and demoralize a civilian population. States willpursue online espionage but also wreak havoc by crash-ing multiple systems – as did the Russians, allegedly, inEstonia in 2007, with mass denial-of-service attacks ongovernment sites, and in Ukraine in 2016, with cyberattacks on the airport and power grid (Polityuk 2016).

Underlying many of these attacks is terrorism: anattempt to extract political concessions by instillingfear in the civilian population. In this way, cyber ter-rorism is no different from conventional terrorism. Yetcyber terrorism is far more subtle. To date, cyberterrorists have neither killed nor injured anyone. Norhave cyber terrorists successfully destroyed any criticalinfrastructures. Whether this is due to the offensiveinadequacies of the terrorists or the superior defensivecapabilities of the United States and its allies, expertshave yet to decide.

But as the war on cyber terrorism continues, it isincreasingly clear that protecting vital national interestsis only half the battle. Security experts rightly worryabout defending transportation networks, refineries,dams, military installations, hospitals, banks, and gov-ernment offices from cyber attack just as they worryabout defending the same facilities from terroristbombs or ballistic missiles (Lewis 2002). Yet lost inthe haze of cyber warfare is the human dimension.While scholars and policy makers raise concernsabout the dangers that cyber terrorism holds for

CONTACT Michael L. Gross mgross@poli.haifa.ac.il

BULLETIN OF THE ATOMIC SCIENTISTS, 2016VOL. 72, NO. 5, 284–291http://dx.doi.org/10.1080/00963402.2016.1216502

© 2016 Bulletin of the Atomic Scientists

national security, we know little about its effects onhuman security.

Human security emphasizes the conditions neces-sary for a vibrant civil society (Tadjbakhsh 2014). Atthe most basic level, people must be able to live free ofundue fear, anxiety, and trepidation. At a more devel-oped level, civil society requires energetic public dis-course, judicious public policy, and respect for humandignity. Following 9/11, we now recognize that con-ventional terrorism undermines human security evenmore than national security. It is a common truismthat terrorists want a lot of people watching, not a lotof people dead (Jenkins 1975; Lerner et al. 2003). Thedead are few; it is the living whose daily lives aretransformed by the constant fear of impending doom.Conventional terrorism exacerbates feelings of insecur-ity and perceptions of threat that prompt public criesfor protective and militant government policies thatcan short circuit public discourse, intensify intolerancefor dissident views, and infringe on human rights(Boggs 2002; Hirsch-Hoefler et al. 2014). Does cyberterrorism cause similar effects?

At first glance, it seems that it cannot. In theirattempts to formulate the law of cyber warfare, theframers of the Tallinn Manual on the InternationalLaw Applicable to Cyber Warfare remain unconvincedthat cyber attacks that block e-mail, deny service,employ economic coercion, undermine confidence inthe government or economy, or, in their example,“cause panic by falsely indicating that a highly conta-gious and deadly disease is spreading through thepopulation” cause sufficient mental suffering to riseto the level of a terrorist attack (Schmitt 2013, §11.2,3; 30.12; 36.3; 59.9). Unfortunately, these assumptionsare untested and in a series of field experiments westudied how cyber terrorism affects psychological well-being and political attitudes that impinge upon humansecurity by causing stress, anxiety, and fear – all ofwhich radicalize political attitudes and push people toexchange privacy for security to prevent cyber terror inthe future.

Simulating cyber terrorism

In our field survey experiments, we first interviewed522 individuals following Anonymous’s well-publicizedattempt to perpetrate an “electronic Holocaust” inApril 2015, when the hacktivist group promised totake down servers and “erase Israel from cyberspace.” In a second study, in January 2016, 907 subjectsviewed various film clips describing hypotheticalHamas attacks on Israel’s national water company. Inone scenario, cyber terrorism was fatal; terrorists

poisoned the water supply with an overdose of chlorinethat killed two and injured many more. In other sce-narios, cyber terrorism was not lethal; no one sufferedphysical harm but hackers appropriated the bankaccount numbers of the company’s customers and suc-cessfully transferred money to Hamas. A third group ofsubjects viewed a fatal but conventional mass-casualtyterrorist attack, while a control group viewed a neutralfilm depicting the dedication of a water treatmentplant. Following these screenings, we surveyed respon-dents on measures fundamental to human security.These included stress, anxiety, insecurity and threatperception, political militancy, and a willingness torelinquish privacy.

In someways, Israelis are a unique population for sucha study. The ongoing conflict between Israelis andPalestinians (and Palestinian allies like Hezbollah andIran) is a constant feature of everyday life. Terrorism,too, simmers beneath the surface. In the 18 monthssince January 2015, terrorists have taken 30 civilian livesin Israel and the West Bank (B’Tselem 2016). Yet Israelisknow their enemy, know what they want, and can ima-gine the way to peace. This puts terrorism and cyberterrorism in the context of a political struggle that has,in many ways, fixed and acceptable costs. Like a couple ofwary boxers, each side circles the other, constantly pokingand provoking. This leaves Israelis, who score very highon the UN’s world happiness index, weary but resilient.

In contrast, theWest’s confrontation with radical Islamis enigmatic and exceptionally violent. In the same 18month period, 68 Americans and 269 Europeans havelost their lives in terrorist attacks (Indian Express 2016;International Security 2016; McHugh 2016). UnlikeIsraelis, Americans and Europeans don’t know theirenemy, have no clear idea what they want or how toconfront their demands. Islamic State attacks are brutallyviolent for their own sake. Americans and especiallyEuropeans will find resilience elusive as terrorism andcyber terrorism fuel an inescapable cycle of fear.Learning from the Israeli case and understanding theeffects of cyber terrorism for other Western nations arecrucially important.

Measuring stress and insecurity

Not surprisingly, exposure to cyber terrorism is stress-ful. Figure 1 uses the State-Trait Anxiety Inventory(STAI) to show how stress and anxiety grow as attacksbecome more deadly. With a score of 4.00, conven-tional mass-casualty terrorism (e.g. suicide bombings)evokes a level of anxiety at the top of the scale. Thestress scores for lethal and nonlethal cyber terrorismare not far behind, and all the scores significantly

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surpass the control group. But the interesting point isthis: Individuals were equally disturbed by lethal andnonlethal cyber terrorism, meaning there is no signifi-cant difference between the two when it comes tostress. Both cause significant panic and anxiety andboth, it seems, are equally capable of cracking thefoundations of personal well-being and humansecurity.

Cyber terrorism also left individuals insecure andwary of future cyber terrorist attacks. These judgmentsare measures of threat perception and gauged by suchquestions as: “To what extent do cyber attacks under-mine your sense of personal security?” and “To whatextent do you feel threatened by cyber terrorism?” Likestress, threat perception increased steadily as attacksgrew more severe (Figure 2). But even in our controlgroup, Israelis are on edge, and exposure to nonlethalcyber terrorism did not appreciably increase perceptionsof threat. Lethal attacks, on the other hand, did trigger asignificant jump in threat perception and it didn’t mat-ter much whether they were cyber or conventional ter-rorist attacks. These findings show how stress and threatperception are two different phenomena. Stress is emo-tional while threat perception is cognitive. And whilelethal and nonlethal cyber attacks evoke feelings ofstress, only terrorism accompanied by injury and lossof life nurtures a serious preoccupation about the nextattack. If a person’s reaction to cyber terrorism has both

an emotional and cognitive dimension, it is also sensi-tive to circumstance and the identity of the perpetrator.After it was clear that Anonymous’s threat of an “elec-tronic Holocaust” was empty, threat perception fell by10%. People were still fearful, but not so much. Butmany Israelis do fear Hamas. And when that group,rather than Anonymous, was the perpetrator, threatperceptions increased by 20%, from a mean score of2.9 to a score of 3.5. Hamas is a far more frighteningadversary than Anonymous, even as they perpetratesimilar attacks.

Stress, anxiety, insecurity, and perceptions ofthreat do not stand alone. Instead, we know thatstudies of conventional terrorism show how stress,anxiety, and heightened perceptions of threat radica-lize political attitudes and draw individuals awayfrom concerns about civil liberties to worries aboutnational security (Verton and Brownlow 2003). Inthe wake of mass-casualty terrorism, individualsturn inward, disparage outgroups, move to the righton security and privacy issues, and call upon theirgovernment to take strong military action (Canettiet al. 2013; McDermott 2010). The effects can have achilling effect on civil society and political discoursein many democratic nations, as debates about tor-ture, rendition, due process, military belligerency,and surveillance show. We were not surprised tosee similar effects from cyber terrorism.

Figure 1. Anxiety in the wake of terrorism.

286 M. L. GROSS ET AL.

Political reactions

Figures 3 and 4 depict an array of political attitudes thatharden in the wake of terrorism. As noted, individuals inour first survey confronted an ongoing cyber attack byAnonymous and in the second, a simulated attack byHamas. In each case, we asked individuals about theirsupport for internet surveillance, government regulation,and military retaliation in the context of an unspecifiedcyber terror attack. Questions centered on surveillance andcivil liberties (“Should the government monitor emails andsocial networks for suspicious phrases?”; “Are you willingto let the government read emails to improve personal andnational security?”),1 government regulation (“Should thegovernment require businesses to install cyber securitysystems?”), and military retaliation (“Following a cyberterrorism attack, should the government respond with asmall-scale cyber attack against military targets, a large-scale cyber attack against military and civilian targets, asmall-scale conventional (missiles, bombs, and artillery)attack against military targets, or a large-scale conventionalattack attacks against military and civilian targets?”)

Attitudes varied depending on the perpetrator. WhenAnonymous was the attacker, 54% of the respondents inour survey would allow the government to monitor

e-mails for suspicious phrases, 48% would allow thegovernment to monitor Facebook and Twitter, and 23%would allow the government to read e-mails. When theperpetrator was Hamas, support for government surveil-lance leaps to 67% in favor of monitoring e-mails, 46% infavor of monitoring social media, and 61% in favor ofreading e-mails. Among Americans in general, by con-trast, only 43% of the respondents would allow the USgovernment to monitor the communications of US citi-zens (Shelton, Rainie, and Madden 2015, 6). AmongIsraelis, support for surveillance depends on the identityof the perpetrator. And while the identity of the attackerdid not affect calls for government regulation (74% of therespondents would require business to install cyber secur-ity software) fears of Islamic terrorism dominate thepublic’s demand for military responses. As Figure 4demonstrates, individuals facing Hamas terrorism wereconsiderably more militant and supported conventionalretaliation by a margin of nearly 2:1 compared to thosefacing the hacktivist group Anonymous. One reason maybe greater fear of Hamas but another may be the recogni-tion that Hamas, like Islamic State, has infrastructuresand territory vulnerable to conventional attack. On theother hand, it is fear of Hamas rather than its vulner-ability that drives greater support for surveillance. These

Figure 2. Threat perception and insecurity.

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data highlight the public’s willingness to employ conven-tional military measures to quash cyber terrorism, strongattitudes that will no doubt influence political leaders asthey weigh kinetic military responses to cyber threats(Libicki forthcoming).

From a psychological perspective, the data offer acurious finding. We expected to find a clear connection

between exposure to cyber terrorism and militant,hardline attitudes. The harsher the terrorist attack oursubjects experienced, the greater their militancy. Butthis is not what we discovered. Instead, we found thatthe greater one’s perception of threat, the greater one’smilitancy. The odds were more than twice as high thatindividuals with high levels of threat perception will

Figure 4. Percent favoring small-scale and large-scale or conventional retaliation.

Figure 3. Percent favoring surveillance and government regulation.

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support surveillance, government regulation, and mili-tary retaliation compared to those whose threat percep-tion is lower. We cannot explain why some individualsare more fearful than others. Past exposure to cyberattacks explains only a small part of the variance. Otherpersonality factors, beyond the scope of our study toexamine, are also probably at work. Nevertheless, it isclear that the threat of terrorism and how one perceivesit are better determinants of militancy and hardlineattitudes than the experience of an actual attack. And,indeed, this is how terrorism works. One need notsuffer direct harm to be terrorized; it is enough thatone fear direct harm to suffer the ravages of contem-porary terrorism, whether cyber terrorism or conven-tional terrorism.

From Anonymous and Hamas to Islamic state

These results offer tantalizing evidence that cyber ter-rorism mirrors conventional terrorism even when itsvictims do not suffer injury or loss of life. We foundthat cyber terrorism increases stress, anxiety, fear, hard-line attitudes, and political militancy. But circumstancesmatter, because the identity of the perpetrator helpsexplain the political attitudes related to cyber terrorism.Hamas is more threatening than Anonymous. WhenHamas is at the wheel, Israelis see a brutal terroristorganization and do not much distinguish betweencyber and conventional terrorism. Anonymous, on theother hand, still carries some cachet as a rogue hacktivistgroup that is unwilling or unable to harm anyone phy-sically. Hamas, for the most part, poses no threat toAmericans and Europeans. But Islamic State certainlydoes, and it will not be long before the group gains thecapabilities to mount cyber-terrorism attacks. And, aswith Hamas, the fact that these attacks might cause littlephysical harm may be irrelevant. Islamic State, likeHamas, will trade on its ruthless terrorist image.Leveraging its success at conventional terrorism, it willmove seamlessly and effectively to cyber terrorism toproduce outsized fear and panic. Marrying conventionaland cyber terrorism will have chilling effects: IslamicState and other terrorist groups will be able to achievethe dramatic effects of suicide attacks and mass casual-ties at the relatively low cost and risk of cyber terrorism.There will be no need for suicide cyber bombers. Cyberterrorism is a force multiplier that can magnify theeffects of limited, sporadic, and even failed kinetic ter-rorist attacks. In tandem, conventional and cyber terror-ism can undermine human security in a mostfundamental way.

Restoring human security

Human security thrives when societies are open, toler-ant, peaceful, and vibrant, and when they offer citizensthe conditions necessary to flourish economically, intel-lectually, physically, and emotionally (Tadjbakhsh andChanoy 2007). Physical security is a necessary conditionfor human security but not sufficient if civil society failsto allow its members to thrive. To thrive, individualsmust maintain tolerance and social discourse. By indu-cing stress and anxiety, cyber terrorism endangers psy-chological well-being and increases perceptions of threateven if individuals suffer no physical harm. Once cyberterrorism successfully breaches a critical infrastructureto kill and injure (as in our film clips), these effects aremore pronounced. Threat perception is not all bad.Reasonable perceptions of threat are essential to protectindividuals and their communities from dangerous sur-prises but become disabling when they foster insecurityand prompt visions of an inescapable cycle of violence(Canetti-Nisim et al. 2009). It is the nature of cyberterrorism to target civilians (Gross 2015, 153–183).Some of this is mere efficiency: Civilian targets are softerthan military targets or critical infrastructures, whichstates take great pains to protect. But part is strategic:Targeting civilians is a way to demoralize and terrorize.This is precisely what Anonymous, Hamas, and IslamicState promise to do.

In response, civilians are increasingly willing to jet-tison privacy and support military retaliation. Neitheroutcome bodes well for human security. Privacyembraces the right to keep secrets and preserves adomain for individuals to build their personal identitiesand communicate without interference or duress.Surveillance inhibits free speech, discourages politicalopposition, prevents dissenters from organizing orpublishing anonymously, and disrupts the flow ofinformation necessary for a well-functioning civilsociety. Surveillance threatens privacy but not withoutcause. Surveillance can strengthen physical security.Gaining access to the content of e-mails and socialmedia may allow law enforcement authorities andintelligence agencies to co-opt and cripple hostile orga-nizations. Physical security is as important for humansecurity as privacy. Balancing the two will be excep-tionally challenging in the shadow of cyber terrorism,and cyber security experts and policy makers cannotunilaterally fortify the former at the expense of thelatter.

Political militancy is equally problematic. Facingcyber terrorism and the threat it poses to nationaland human security, governments consider a range of

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tempered policies that include criminal prosecution,counter espionage, and active cyber defenses. Becausemost offensive cyber attacks fall far short of war, eachof these retaliatory responses is freighted with fears ofescalation that the United States and other nations wishto avoid. Nations must be careful as they weigh theirresponses to hostile cyber operations (Hathaway et al.2012). Civilians, particularly those who already findthemselves in the midst of an armed conflict, are lessrestrained and may push their governments in unwar-ranted and dangerous directions as they call for harshmilitary retaliation following cyber attacks. Humansecurity does not demand pacifism but it thrives bestin a society that is cautious about the use of armedforce. Cyber terrorism, like conventional terrorism,upends judicious decision making.

Eliminating the toxic effects of cyber terrorism isnot simply a matter of cyber security. It is not enoughto thwart or reduce the incidence of cyber-terrorattacks. Protecting facilities is only half the battle.Fear, insecurity, anxiety, and militancy are often theproduct of perceived, not actual, threats. Cyber terror-ists lurk in the background, and individuals will not bemollified unless they are eliminated. Despite their bestefforts, however, no government will ever eradicatecyber terrorism, and people will always be driven bytheir outsized fears. Mitigating these fears is as equallyimportant as reducing the incidence of attack. But themeans are entirely different. Perceptions depend cru-cially on information and, as a result, risk assessmentand communication are of crucial importance in thewar against cyber terrorism. Individuals who misun-derstand the nature of cyber terrorism and the threat itposes are most likely inclined to greater fear, insecurity,and militancy than those whose assessment is sober.Experts, to be sure, remain divided over the risk ofcyber terrorism. Nevertheless, the cyber security com-munity must address the fears of everyday citizens bycogently assessing the danger of cyber terrorism andthe protective measures necessary to maintain securenetworks. Risk communication is sorely lacking; prop-erly implemented, it can reduce insecurity and percep-tions of threat. Finally, there is also room to thinkabout psychological intervention and cognitive beha-vior therapy to treat cyber terrorism-induced anxieties,just as it is used to treat the effects of conventionalterrorism.2 Risk assessment and psychological treat-ment protocols address the human dimension ofcyber terrorism and should not be neglected as nationswork to fend off cyber terrorists of all stripes.

Cyber terrorism has many faces, as does the psy-chology of the masses. Our research demonstrates howeven nonlethal, seemingly banal forms of cyber

terrorism have a considerable impact on the attitudesof victimized populations. Our experiments show a“cyber terrorism effect” that can enable terrorists tofoster fears akin to kinetic terrorism and pursue simi-larly ideological goals. In this way, cyber terrorismpushes well beyond cyber crime even when its methods– identity theft, destruction of data, and disruption ofservice – are sometimes similar. When Anonymousthreatens an electronic Holocaust by corrupting dataor stealing identities, they are taking sides in violent,armed conflict, and their actions are far more thancriminal. They are attacking innocent civilians, notbilking an easy mark. Victims know the difference.Under attack, they react not only with fear and trepi-dation, as do victims of crime, but also with demandsfor protection from the enemies of the state via harshmilitary retaliation, surveillance, and strong govern-ment. This is the psychology of terrorism.

Notes

1. “Reading” and “monitoring” are different. “Monitoring”suggests either the collection of metadata or only read-ing e-mails that trigger security concerns, while “read-ing” suggest scrutinizing every e-mail.

2. For example, see Somer et al. (2005).

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

This research was made possible, in part, by grants awardedto Daphna Canetti from the US National Institute of MentalHealth [R01 MH073687], from the Israel Science Foundation[594/15], and from the US-Israel Binational ScienceFoundation [2009460], and to Michael L. Gross from theIsrael Science Foundation [156/13].

Notes on contributors

Michael L. Gross is a professor in and the head of the Schoolof Political Science at the University of Haifa, Israel. Hisrecent books include The Ethics of Insurgency (Cambridge2015), Moral Dilemmas of Modern War (Cambridge 2010)and the forthcoming, Soft War: The Ethics of UnarmedConflict (Cambridge).

Daphna Canetti is a professor of political science at theUniversity of Haifa and the director of the university’s grad-uate program in Democracy Studies. Canetti’s researchexamines the psychological challenges and policy implica-tions of terrorism, warfare, and political violence. Her pub-lications appear in political and psychological outletsincluding the Lancet, the American Journal of Political

290 M. L. GROSS ET AL.

Science, the British Journal of Political Science, and PoliticalPsychology. Her commentary has been featured in mediaoutlets including NPR and the Washington Post.

Dana Vashdi is the head of the Division of PublicAdministration and Policy at the University of Haifa, Israel.Her research focuses on the well-being of citizens in generaland of employees in particular as well as on teams in publicorganizations, organizational learning, and healthcare policy.She has published articles in a wide variety of academicjournals including the Academy of Management Journal,British Medical Journal, Human Resource Management, andPublic Administration Review.

ORCID

Michael L. Gross http://orcid.org/0000-0001-5835-7879Daphna Canetti http://orcid.org/0000-0003-0794-4090Dana R. Vashdi http://orcid.org/0000-0003-3644-2129

References

Boggs, C. 2002. “Militarism and Terrorism: The DeadlyCycle.” Democracy & Nature 8 (2): 241–259. doi:10.1080/10855660220148598.

B’Tselem. 2016. “Fatalities after Operation Cast Lead.”B’Tselem - The Israeli Information Center for HumanRights in the Occupied Territories. http://www.btselem.org/statistics/fatalities/after-cast-lead/by-date-of-death.

Canetti, D., B. J. Hall, C. Rapaport, and C. Wayne. 2013.“Exposure to Political Violence and Political Extremism: AStress-Based Process.” European Psychologist 18 (4): 263–272. doi:10.1027/1016-9040/a000158.

Canetti-Nisim, D., E. Halperin, K. Sharvit, and S. E. Hobfoll.2009. “A New Stress-Based Model of Political Extremism:Personal Exposure to Terrorism, Psychological Distress,and Exclusionist Political Attitudes.” Journal of ConflictResolution 53 (3): 363–389. doi:10.1177/0022002709333296.

Gross, M. 2015. The Ethics of Insurgency: A Critical Guide to JustGuerrilla Warfare. Cambridge: Cambridge University Press.

Hathaway, O. A., R. Crootof, P. Levitz, H. Nix, A. Nowlan,W. Perdue, and J. Spiegel. 2012. “The Law of Cyber-Attack.” California Law Review 100 (4): 817–885.

Hirsch-Hoefler, S., D. Canetti, C. Rapaport, and S. E.Hobfoll. 2014. “Conflict will Harden Your Heart:Exposure to Violence, Psychological Distress and PeaceBarriers in Israel and Palestine.” British Journal ofPolitical Science 1–15. doi:10.1017/S0007123414000374.

Indian Express, 2016. “List of Terrorist Attacks that haveStruck Europe in 2016.” Indian Express. http://indianexpress.com/article/world/world-news/list-of-terrorist-attacks-that-have-struck-europe-in-2016/.

International Security, 2016. “Deadly Attacks Since 9/11.”International Security. http://securitydata.newamerica.net/extremists/deadly-attacks.html.

Jenkins, B. M. 1975. “Will Terrorists Go Nuclear?” P-5541 inthe RAND Paper Series. Santa Monica, CA: The RANDCorporation.

Lerner, J. S., R. M. Gonzalez, D. A. Small, and B.Fischhoff. 2003. “Effects of Fear and Anger onPerceived Risks of Terrorism: A National FieldExperiment.” Psychological Science 14 (2): 144–150.doi:10.1111/psci.2003.14.issue-2.

Lewis, J. A. 2002. Assessing the Risks of Cyber Terrorism,Cyber War and Other Cyber Threats. Washington, DC:Center for Strategic and International Studies, December.

Libicki, M. C. forthcoming. ““From the Tallinn Manualto Las Vegas Rules.” Chap. 32.” In Cyberspace in Peaceand War. Annapolis, MD: Naval Institute Press, 2016.

McDermott, R. 2010. “Decision Making under Uncertainty.”In Proceedings of a Workshop Deterring Cyberattacks:Informing Strategies and Developing Options for U.S.Policy, National Research Council, 227–241. Washington,DC: The National Academies Press.

McHugh, J. 2016. “Europe Terrorist Attacks 2016.” IBT, March24. http://www.ibtimes.com/europe-terrorist-attacks-2016-timeline-bombings-terror-threats-brussels-2341851.

Polityuk, P. 2016. “Ukraine Sees Russian Hand inCyber Attacks on Power Grid.” Reuters, February 12.http://www.reuters.com/article/us-ukraine-cybersecurity-idUSKCN0VL18E.

Rogers, A. 2014. “What Anonymous is Doing in Ferguson.”Time, August 21. http://time.com/3148925/ferguson-michael-brown-anonymous/.

Schmitt, M. N., ed. 2013. Tallinn Manual on the InternationalLaw Applicable to Cyber Warfare. Cambridge: CambridgeUniversity Press.

Shelton, M., L. Rainie, and M. Madden. 2015. “Americans’Privacy Strategies Post-Snowden.” Pew Research Center,March 15. http://www.pewinternet.org/files/2015/03/PI_AmericansPrivacyStrategies_0316151.pdf.

Somer, E., E. Tamir, S. Maguen, and B. T. Litz. 2005. “BriefCognitive Behavioral Phone-Based Intervention TargetingAnxiety about the Threat of an Attack: A Pilot Study.”Behaviour Research and Therapy 43 (5): 669–679.doi:10.1016/j.brat.2004.05.006.

Tadjbakhsh, S. 2014. “Human Security Twenty Years on.”Norwegian Peacebuilding Resource Centre (NOREF), June.http://www.peacebuilding.no/var/ezflow_site/storage/original/application/540cb240aa84ac7133bce008adcde01f.pdf.

Tadjbakhsh, S., and A. M. Chanoy. 2007. Human Security:Concepts and Implications. Abingdon, UK: Routledge.

Verton, D., and J. Brownlow, eds. 2003. Black Ice: TheInvisible Threat of Cyber-Terrorism. Emeryville, CA:McGraw-Hill/Osborne.

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