Public Responses to Jihadist Terrorism on Social Media

European Survey Research Association conference 2025, Utrecht University

Christian S. Czymara (Netherlands Interdisciplinary Demographic Institute)

18 Jul 2025

Introduction

  • Social media shapes how societies respond to terrorist attacks
    • Emotional expression and political discourse (Bove et al. 2024; Hurtado Bodell & Menshikova 2024)
    • Increases in both hate speech (Czymara & Gorodzeisky 2024; Kaakinen et al. 2018) and solidarity (Garcia & Rimé 2019)
    • Offline effects: Far-right voting (Giavazzi et al. 2023), hate crimes (Müller & Schwarz 2021)
  • Research question: How do immigration-related discussions evolve on Twitter after Jihadist attacks?

Terror Management Theory

  • Fear of death leads people to defend cultural worldviews (Greenberg et al., 1986; Yum & Schenck-Hamlin 2005; Fischer-Preßler et al., 2019)
  • After terrorist attacks, reactions include:
    • Religious behavior, nationalism, prejudice/stereotyping
    • Counterbigotry activism, altruism, appreciation of helpers
  • Focus of this study on reactions relating to migration or intergroup relations

Topic Expectations: Nationalism & Prejudice

  • Group threat theory: majorities may view minorities as threats after “significant events” (Blumer, 1958)
  • Jihadist terror attacks can trigger exclusionary views (Legewie, 2013)
  • TMT categories:
    • Prejudice/stereotyping: Negative outgroup sentiment
    • Nationalism/patriotism: Positive ingroup sentiment

Topic Expectations: Prosocial Behavior & Counterbigotry

  • Reactions to terror attacks can also include empathy, tolerance, and solidarity
  • Shared trauma can strengthen intergroup bonds (social resilience) (Garcia & Rimé, 2019)
  • TMT categories:
    • Prosocial behavior: Empathy, emotional support
    • Counterbigotry activism: Calls for tolerance, rejection of hate

The Dynamic Nature of Topics

  • Online reactions to terrorism shift over time
    • Hate speech and negative emotions peak early, then decline (Czymara & Gorodzeisky, 2024; Garcia & Rimé, 2019)
    • Solidarity and opinion-driven content emerge later (Fischer-Preßler et al., 2019)
  • Nationalism and prejudice are expected to peak early, followed by a rise in prosocial behavior and counterbigotry

Overview of attacks

City Date Attack Deaths Injuries Abbreviation
Paris (FR) 7–9 Jan 2015 Charlie Hebdo + kosher supermarket shootings 17 19 FR15_CH
Paris (FR) 13 Nov 2015 Bataclan shootings and other attacks 137 413 FR15_BATA
Brussels (BE) 22 Mar 2016 Airport and metro station bombings 32 340 BE16
Nice (FR) 14 Jul 2016 Bastille Day truck attack 87 270 FR16
Berlin (DE) 19 Dec 2016 Christmas market truck attack 13 48 DE16
London (UK) 22 Mar 2017 Westminster Bridge attack 5 48 UK17_west
Manchester (UK) 22 May 2017 Manchester Arena bombing 22 239 UK17_man
London (UK) 3 Jun 2017 London Bridge attack 8 48 UK17_lon
Barcelona (ES) 17 Aug 2017 Van attacks 15 104 ES17
Strasbourg (FR) 11 Dec 2018 Christmas market attack 5 11 FR18
Vienna (AT) 02 Nov 2020 Shootings 5 22 AT20

Search string

  • Identify Tweets that deal with migration related topics, including Muslims (much debated migrant group), but no direct search for insults or derogatory terms, nor attack specific hashtags
  • Language-specific search string, English version (all accessible at osf.io/zdt5b):
 [1] "migration"   "immigration" "migrant"     "immigrant"   "foreigner"  
 [6] "migrants"    "immigrants"  "foreigners"  "refugee"     "refugees"   
[11] "asylum"      "islam"       "islamist"    "islamism"    "muslim"     
[16] "muslims"     "salafist"    "Salafism"    "jihad"
  • Accounts located in the city of each attack took place

Distribution of Tweets

  • 102173 Tweets posted by 36390 accounts

Method

Keyword-Assisted Topic Modelling

  • keyATM (Eshima et al., 2024) is a semi-supervised model using predefined keywords (identifying both expected and unexpected topics)
  • Uses keywords to initialize the model, which then refines the topics based on the data
  • Reduces subjectivity by directly targeting theoretical concepts
  • Less sensitive to topic number specification

Topic Identification

  • Focus on TMT reactions tied to intergroup dynamics:
    • Nationalism: National pride, anti-immigrant sentiment
    • Prejudice: Stereotypes of minorities as violent or threatening
    • Counterbigotry: Rejection of hate, emphasis on tolerance and solidarity
    • Prosocial: Empathy and support for victims and affected communities

Keywords

  • Keywords selected based on prior research and empirical validation
Language Nationalism Prejudice Counterbigotry Prosocial
English proud, tradition, culture, patriot, patriotic criminal, danger, illegal, violence, violent, threat, barbarism love, peace, tolerance, racist, racism, solidarity victims, relatives, thoughts, condolences, sympathy, mourn
French fier, fière, fiers, culture, tradition, patriote, patriotique criminelle, illégale, violence, violente, menace, barbarie amour, paix, tolérance, raciste, racisme, solidarité victimes, proches, pensées, condoléances, sympathies, deuil
German stolz, tradition, kultur, patriot, patriotisch, volk kriminell, gefahr, illegal, gewalt, gewalttätig, bedrohung, barbarei liebe, frieden, toleranz, rassist, rassismus, hetze, solidarität opfer, angehörige, gedanken, gedenken, beileid, trauer
Spanish orgulloso, tradición, cultura, patriota, patriótico criminal, peligro, ilegal, violencia, violenta, amenaza, barbarie amor, paz, tolerancia, racista, racismo, solidaridad victima, relatives, pensamientos, condolencia, pésame, dolor

Final Model

  • Lowercasing, stemming, removing stopwords, top 15 most frequent terms per language, @mentions, punctuation, numbers, symbols, URLs
  • Covariate keyATM to examine temporal variation: Dummy predictor (first 2 days vs. days 3–7)
  • In addition to 4 keyword-based topics, 20 non-keyword topics estimated
  • Separate models for each language

Validation

  • Annotated 150 most representative Tweets for each topic-language combination (based document-topic distribution \(\theta\))
  • Zero-shot classification with GPT-3.5-turbo-0125 with manually validation
  • On average, each topic overlapped 70 percent with the GPT classification
    • 49 percent (Nationalism in English, Prosocial in French)
    • 89 percent (Prejudice in French and German)

Results

keyATM Results: English

   1_nationalism 2_prejudice 3_counterbigotry 4_prosocial Other_1 Other_2
1     cultur [✓]      muslim           muslim      muslim  muslim  immigr
2         muslim       islam            islam      attack  immigr  brexit
3         immigr violent [✓]         peac [✓]  victim [✓]   islam      eu
4          islam violenc [✓]         love [✓]      london  refuge  refuge
5         refuge        true       racist [✓]       islam  attack  muslim
6         migrat        call            peopl      terror  brexit migrant
7     tradit [✓]        rape         religion   terrorist migrant  migrat
8        migrant  crimin [✓]        terrorist       peopl   peopl    vote
9       religion  threat [✓]           terror   westminst countri foreign
10         chang   illeg [✓]             hate   communiti british    leav
     Other_3   Other_4   Other_5   Other_6  Other_7 Other_8 Other_9  Other_10
1     muslim    muslim    muslim    immigr   muslim  muslim  muslim    muslim
2      islam     islam     islam    muslim    islam  immigr  refuge     islam
3     terror    refuge    repres    refuge   refuge  refuge  immigr     peopl
4     refuge     peopl     peopl        eu  migrant migrant   islam terrorist
5     attack    attack    attack   migrant   immigr   islam migrant      kill
6     action      kill terrorist     islam    peopl  migrat  migrat    attack
7     london terrorist    terror    migrat   attack    vote   stori    terror
8    condemn    london    immigr    brexit     fear  brexit  asylum    london
9  terrorist    terror    london contribut   terror  asylum  brexit christian
10       pls    immigr       cox   economi islamist      eu support    immigr
    Other_11  Other_12  Other_13  Other_14 Other_15  Other_16 Other_17
1     muslim    muslim    muslim    muslim   refuge    muslim   muslim
2     refuge     islam     islam     islam   muslim     islam   immigr
3     immigr    attack terrorist    immigr  migrant     peopl   refuge
4      islam terrorist     peopl    refuge     boat terrorist    islam
5    migrant     peopl    attack     peopl    islam    immigr  migrant
6     migrat    london    terror    terror    rescu    terror   migrat
7     asylum    immigr      kill    attack     rais    attack       eu
8  contribut    terror   british    migrat   immigr christian     vote
9     london      kill    london terrorist   target  islamist   asylum
10      news  islamist   ramadan      read      med      kill    women
    Other_18  Other_19 Other_20
1     muslim    muslim   muslim
2      islam     islam    islam
3  terrorist    attack   immigr
4     immigr     bridg   refuge
5      peopl     women   london
6       fuck westminst    peopl
7       alex   condemn  migrant
8       jone    london   terror
9     attack    gather   attack
10    refuge terrorist islamist

keyATM Results: French

   1_nationalism  2_prejudice 3_counterbigotry  4_prosocial  Other_1  Other_2
1          islam   barbar [✓]         musulman     musulman musulman musulman
2         djihad     musulman         paix [✓]   victim [✓]    franc   réfugi
3       musulman    menac [✓]          l'islam        c'est    islam   djihad
4          franc      l'islam            c'est     pens [✓]   djihad   syrien
5     cultur [✓]        islam         religion      l'islam    c'est    franc
6      anonymous        franc           terror       terror  l'islam    islam
7            sit  violenc [✓]            islam        islam   terror   terror
8        l'islam       terror       racist [✓]        franc    charl  l'islam
9          charl criminel [✓]             juif charliehebdo    paris    paris
10         jihad         acte            franc        qu'il    hebdo attentat
    Other_3      Other_4  Other_5  Other_6  Other_7  Other_8  Other_9
1  musulman     musulman    franc   djihad musulman   djihad musulman
2     franc        islam   djihad musulman   djihad    islam    c'est
3     c'est      l'islam musulman    islam    franc musulman    franc
4   l'islam        franc   réfugi   terror    islam    franc    islam
5     islam        c'est    islam    jihad  l'islam    jihad  l'islam
6    terror       terror    jihad    franc étranger attentat   djihad
7      juif       djihad attentat    drogu    c'est    paris   terror
8     charl        charl étranger captagon   réfugi   terror    qu'il
9    djihad     étranger   terror     publ    charl    salaf     faut
10    qu'il charliehebdo    paris     fatw   terror étranger     fair
       Other_10 Other_11 Other_12 Other_13 Other_14  Other_15 Other_16 Other_17
1      musulman musulman musulman musulman musulman  musulman musulman musulman
2         charl    franc    c'est    c'est   djihad      mond    franc   djihad
3         franc    islam  l'islam  l'islam    islam     lettr    islam    franc
4         islam   djihad    islam    islam    franc     franc     fair    islam
5       l'islam étranger   terror   terror    jihad     islam   djihad    jihad
6  charliehebdo    c'est    franc    franc    c'est     bidar  l'islam    paris
7     caricatur  l'islam    qu'il   djihad  l'islam abdennour attentat attentat
8      étranger   terror   djihad    qu'il    moder   l'islam    daesh   terror
9         hebdo attentat     fair       tu      sit    djihad   réform  l'islam
10        daesh    polit     faut     fair     fair      juif  théolog   lassan
   Other_18 Other_19  Other_20
1  musulman musulman    djihad
2     franc   djihad  musulman
3   l'islam    islam     islam
4     islam    franc anonymous
5     c'est   terror     franc
6    terror  l'islam     compt
7    djihad    c'est     twitt
8     lieux    jihad     paris
9      cult   réfugi       sit
10 étranger étranger   l'islam

keyATM Results: German

   1_nationalism  2_prejudice 3_counterbigotry  4_prosocial          Other_1
1           asyl   gewalt [✓]         hetz [✓]      opf [✓]     flucht­lin­g
2           turk  illegal [✓]    rassismus [✓]       muslim            islam
3    deutschland   gefahr [✓]        fried [✓]     trau [✓]           berlin
4      stolz [✓]       muslim           muslim   gedenk [✓]       asylbewerb
5         turkei flucht­lin­g            islam        islam           muslim
6       beantrag    migration         lieb [✓]       berlin         anschlag
7         muslim    einwander       islamismus flucht­lin­g           terror
8   flucht­lin­g         asyl     flucht­lin­g     anschlag        terrorist
9          islam         wien           terror     islamist breitscheidplatz
10          land     turkisch            glaub       terror      deutschland
        Other_2      Other_3      Other_4      Other_5          Other_6
1  flucht­lin­g flucht­lin­g        islam flucht­lin­g     flucht­lin­g
2        terror      deutsch       muslim        islam           berlin
3         islam        islam flucht­lin­g        polit       asylbewerb
4          fakt         grun   islamismus   islamismus            islam
5        merkel   islamismus       terror         wien breitscheidplatz
6   faktencheck       muslim       berlin       terror           falsch
7      religion      migrant        polit         pass           mosche
8        berlin        probl       europa       muslim             syst
9   terrorismus    migration     islamist     speziell       islamismus
10   islamismus  deutschland  unterschied          spd           terror
            Other_7      Other_8      Other_9       Other_10     Other_11
1      flucht­lin­g        islam       muslim   flucht­lin­g flucht­lin­g
2            berlin        polit        islam         muslim        islam
3  breitscheidplatz       muslim         wien          islam     reaktion
4          anschlag flucht­lin­g   islamismus          polit     anschlag
5              fahr     turkisch flucht­lin­g           wien         asyl
6               lkw         wien       moslem        ausland     dringend
7             islam gesellschaft      polizei terroranschlag       muslim
8            merkel    terrorist       europa      extremist       person
9   weihnachtsmarkt         jung       regier           klar         wahl
10           muslim       moslem         sieh      verurteil         mosl
       Other_12         Other_13     Other_14     Other_15   Other_16
1  flucht­lin­g     flucht­lin­g flucht­lin­g flucht­lin­g      islam
2        muslim           berlin      migrant        islam      polit
3         islam           merkel       europa       terror     muslim
4     migration breitscheidplatz       muslim       merkel islamismus
5          asyl         attentat        polit         asyl   islamist
6        flucht         munition         asyl     religion     terror
7      freundin           muslim    migration   islamismus  migration
8        bekomm             wien        thema         fakt       land
9        schwer       gefluchtet  illegal [2]  faktencheck     turkei
10   gefluchtet             kauf       jahrig       muslim      saudi
       Other_17     Other_18   Other_19       Other_20
1        pegida        islam     muslim   flucht­lin­g
2  flucht­lin­g       muslim osterreich         terror
3         islam flucht­lin­g     behord          islam
4           afd       moslem       wien         muslim
5          asyl         wien   islamist         berlin
6           npd    terrorist        tat         schutz
7        berlin         leut   munition        ausland
8       deutsch       terror   slowakei           land
9    asylbewerb     religion       kauf terroranschlag
10  deutschland       christ     berlin     islamismus

keyATM Results: Spanish

   1_nationalism  2_prejudice 3_counterbigotry 4_prosocial  Other_1  Other_2
1     cultur [✓]   amenaz [✓]         musulman    musulman    yihad musulman
2       musulman     musulman            islam  victim [✓] musulman    yihad
3     orgull [✓] violenci [✓]          paz [✓]      terror     moss   terror
4          islam        islam           terror       islam      via    atent
5         inmigr  violent [✓]       racist [✓]       yihad    polic barcelon
6        necesit        yihad         religion    barcelon    atent    islam
7          abraz       terror         barcelon   dolor [✓] barcelon      via
8           padr        atent       racism [✓]      refugi    alert    celul
9           años         vide         amor [✓]       atent investig    comun
10         muert criminal [✓]            yihad        gent   terror   ripoll
     Other_3   Other_4  Other_5   Other_6   Other_7   Other_8   Other_9
1      yihad  musulman    islam     yihad  musulman  musulman     yihad
2   musulman extranjer musulman       via    terror     yihad     islam
3      islam     yihad    yihad  musulman     yihad     islam  musulman
4     terror     islam    atent    terror     atent extranjer    terror
5      celul   cataluñ   terror      iman       via       odi     atent
6  extranjer     salaf  pregunt     celul  barcelon      habl    refugi
7     refugi    inmigr barcelon extranjer       cre    refugi    explos
8     inmigr     polit     exig     islam     islam    terror  barcelon
9        via    terror  compart      abat     rambl       sig extranjer
10   español   radical     pais      madr arrepient    masacr       via
    Other_10  Other_11  Other_12 Other_13    Other_14   Other_15  Other_16
1   musulman     islam  musulman    yihad   extranjer   musulman  musulman
2  extranjer  musulman     islam    islam    musulman     terror     yihad
3      yihad     yihad    terror musulman       yihad   manifest    terror
4      islam extranjer     yihad   inmigr       islam   barcelon       yih
5        muj      moss     atent  marroqu      inmigr      islam  barcelon
6     refugi  nacional    refugi     años         moz      comun  cataluny
7        mat  investig      pais  catalan      terror      atent extranjer
8    español    refugi extranjer   terror         cas     conden     deten
9       pais     polic       pas    atent independent    cataluñ     islam
10       jov    terror  barcelon    ataqu       mujer antecedent   español
   Other_17 Other_18 Other_19 Other_20
1     islam musulman    islam musulman
2    terror    yihad    yihad    islam
3       cre    islam musulman    yihad
4     frent    españ   terror   terror
5     pasal      via   refugi      mat
6    accion     acus   famili     gent
7    eficaz    atent barcelon    atent
8  musulman     ayud   inmigr      cre
9     yihad   terror religion barcelon
10      via     arab  problem   inmigr

Overall Prevalence of Keyword Topics

Changes in Topics Over Time

Summing up

Conclusion

  • Terrorist attacks can trigger both exclusion and solidarity online
  • Nationalism peaked shortly after attacks, inclusionary topics gained prominence over time
  • Social media reveals shifts not easily captured in survey data
  • Limitations
    • Hate speech likely underrepresented due to platform deletions
    • X’s changing user base (e.g. after Musk’s takeover) likely limits generalizability

Preprint