Does context matter? European-specific risk factors for radicalization

Abstract

In this study we sought to identify whether risk and protective factors for radicalization can be classed as ‘universal’ factors or whether they have heterogeneous cross-regional effects. Specifically, we sought to identify whether there were factors which displayed significantly different effects in European contexts compared to other democratic countries. We conduct a confirmatory meta-analysis based on a recent Campbell Collaboration systematic review and meta-analysis (Wolfowicz, Litmanovitz, Weisburd and Hasisi, 2021). Studies were classified as being from either EU or non-EU countries and moderator analysis was used to identify between-region heterogeneity. The analysis was possible for 23 factors pertaining to radical attitudes, 13 pertaining to radical intentions and 4 for radical behaviours. For radical attitudes, the estimates for European studies were significantly larger for Gender, Socio-economic status, and Parental involvement, whereas the estimates for Religiosity, Institutional trust, Integration, and Moral neutralizations were significantly smaller compared to other democratic countries in other regions. For radical intentions, the estimates for Self-esteem was significantly larger for European studies. For radical behaviours, the estimate for Unemployment was significantly larger for European studies than for democratic countries in other regions. Overall, most risk and protective factors for radicalization appear to have ‘universal’ effects across democratic countries, but there are some factors that may be more relevant for targeting by counter-radicalization in certain contexts. Although European counter-radicalization has often focused on factors such as integration and institutional trust, these factors have relatively small relationships with radicalization, and these relationships are even smaller in the European context compared to democratic countries in other regions. The findings suggest that mitigation strategies, and interventions providing employment opportunities in particular, may be well suited to the European context if the goal is to develop locally-oriented approaches to counter-radicalization.

Full text

Michael Wolfowicz*, David Weisburd and Badi Hasisi
Does context matter? European-specific risk
factors for radicalization
https://doi.org/10.1515/mks-2021-0132
Abstract: In this study we sought to identify whether risk
and protective factors for radicalization can be classed as
‘universal’factors or whether they have heterogeneous
cross-regional effects. Specifically, we sought to identify
whether there were factors which displayed significantly
different effects in European contexts compared to other
democratic countries.
We conduct a confirmatory meta-analysis based on a
recent Campbell Collaboration systematic review and me-
ta-analysis (Wolfowicz, Litmanovitz, Weisburd and Hasisi,
2021). Studies were classified as being from either EU or
non-EU countries and moderator analysis was used to iden-
tify between-region heterogeneity. The analysis was possi-
ble for 23 factors pertaining to radical attitudes, 13 pertain-
ing to radical intentions and 4 for radical behaviours.
For radical attitudes, the estimates for European stu-
dies were significantly larger for Gender, Socio-economic
status, and Parental involvement, whereas the estimates
for Religiosity, Institutional trust, Integration, and Moral
neutralizations were significantly smaller compared to
other democratic countries in other regions. For radical in-
tentions, the estimates for Self-esteem was significantly lar-
ger for European studies. For radical behaviours, the esti-
mate for Unemployment was significantly larger for Eur-
opean studies than for democratic countries in other
regions.
Overall, most risk and protective factors for radicaliza-
tion appear to have ‘universal’effects across democratic
countries, but there are some factors that may be more rele-
vant for targeting by counter-radicalization in certain con-
texts. Although European counter-radicalization has often
focused on factors such as integration and institutional
trust, these factors have relatively small relationships with
radicalization, and these relationships are even smaller in
the European context compared to democratic countries in
other regions. The findings suggest that mitigation strate-
gies, and interventions providing employment opportu-
nities in particular, may be well suited to the European con-
text if the goal is to develop locally-oriented approaches to
counter-radicalization.
1 Introduction
The ways in which democratic countries seek to combat vio-
lent extremism have changed considerably over the last
two decades. Since the mid 2000’s, these countries have in-
creasingly adopted a prevention approach that seeks to
tackle the radicalization that could potentially lead to vio-
lent extremism. It is in this context that we have witnessed a
proliferation of counter and de-radicalization policies and
initiatives. operating at primary, secondary and tertiary le-
vels. Primary level interventions seek to reduce the likeli-
hood of radicalization among the general population or
wide sections of specific sub-populations. At the secondary
level, interventions focus on individuals considered to be at
risk for radicalization, or who have been classified as al-
ready radicalized, with the goal of preventing their progres-
sion to violent extremism. Tertiary level interventions seek
to reduce the likelihood that extremist offenders will re-of-
fend. In all cases, interventions generally seek to counter
radicalization by targeting underlying risk and protective
factors (Hardy, 2020; Silva & Deflem, 2020).
To a large degree, the development of counter-radica-
lization programs has adopted the same type of risk-factor
paradigm that has become popularized over the last few
decades for combatting a range of criminal and crimina-
l-analogous outcomes (Farrington, 2000). Research on
risk and protective factors has sought to identify and es-
tablish which factors have ›universal‹relationships with
such outcomes across contexts, with a view to identifying
which types of interventions may be transferable. In order
to accomplish these objectives, comparative multi-region
and multi-country studies are needed, although they are
unfortunately all too infrequent (Farrington, 2015).
In the development of counter radicalization interven-
tions, and the selection of which factors ought to be tar-
geted, there is a debate concerning the degree to which re-
Open Access. © 2021 Michael Wolfowicz, David Weisburd und Badi Hasisi, publiziert von De Gruyter. Dieses Werk ist lizenziert unter einer
Creative Commons Namensnennung 4.0 International Lizenz.
*Corresponding author: Michael Wolfowicz, Institute of Criminology,
Faculty of Law, Hebrew University of Jerusalem, Israel.
David Weisburd, Hebrew University of Jerusalem, Institute of Crimi-
nology, Faculty of Law, Israel and George Mason University,
Department of Criminology, Law & Society, Faiirfax, VA, USA.
Badi Hasisi, Institute of Criminology, Faculty of Law, Hebrew Univer-
sity of Jerusalem, Israel.
MschrKrim 2021; 104(3): 217–230

gions or countries should draw on the experiences of each
other, or develop more locally relevant approaches. Differ-
ences in the approaches of democratic countries are often
more of a reflection of political, social, and cultural norms
than actual evidence pointing to the specific local relevance
of targeted risk factors (Hardy, 2019; Hasisi, Perry and Wol-
fowicz, 2019). Common norms underpin current ap-
proaches to counter-radicalization in the European Union
(EU). While there is certainly a degree of heterogeneity be-
tween EU member states and even their counter-radicaliza-
tion approaches, all of them are tied to the EU’s counter-ra-
dicalization strategy, which defines radicalization as »the
phenomenon of people embracing opinions, views and
ideas which could [sic] lead to acts of terrorism« (European
Commission, 2005, 2014). In line with this definition, the
European approach to combatting radicalization heavily fo-
cuses on prevention of the development of these ›risky‹cog-
nitions in the context of primary level interventions (Barlett
et al., 2010; Silva & Deflem, 2020). And while different coun-
tries may give greater weight to certain factors over others,
factors such as social inclusion, acculturation and identity
are common across the European Union (Bakker, 2017; Bar-
tlett et al., 2010; Korn, 2016; Proctor, 2019).
In the absence of cross-national and cross-regional
comparative research, criminologists have often turned to
confirmatory meta-analysis, which makes use of modera-
tor analysis in order to examine specific hypotheses, such
as whether risk and protective factor relationships differ
between regions (Farrington et al., 2019; Lösel 2018). This
study employs such an approach and sought to identify
which risk and protective factors for radicalization may
have unique effects in European contexts. Our data are
drawn from a recent systematic review and meta-analysis
of risk and protective factors for radicalization that we
conducted for the Campbell Collaboration (Wolfowicz,
Weisburd, Hasisi and Litmanovitz, 2021). The review in-
cluded some 127 studies and 206 unique samples from
which over 1300 effect sizes were extracted and synthe-
sized across 101 risk and protective factors for both cogni-
tive and behavioral outcomes of radicalization in OECD
countries. In addition to identifying the relative magni-
tude of the estimates for the different factors, the review
also identified study location. In the current study we ana-
lyze European and non-European located studies, employ-
ing both meta-regression and moderator analysis to iden-
tify cross-regional differences between risk factors (e.g.
Pinquart & Kauser, 2018).
The original review found that the most salient factors
of radicalization were, generally speaking, those asso-
ciated with central criminological theories, specifically So-
cial Learning and Social Control theories. While both of
these ›general‹theories hold that risk and protective fac-
tors associated with them ought to have universal effects,
they also account for population heterogeneity, positing
that differences in social structures may lead to cross-re-
gional differences (Gottfredson & Hirschi, 1990; Akers &
Jensen, 2006). We use these theories as a guide for contex-
tualizing regional differences in the effects and discuss the
possible implications of such differences for counter-radi-
calization interventions.
1
2 Cross-regional differences in the
effects of risk factors
The literature on risk factors for radicalization is highly
similar to the broader literature on criminological risk fac-
tors in many ways. One area in which these literatures are
similar is in the relative lack of cross-regional research
(Wolfowicz et al., 2021). While some studies have com-
pared democratic and non-democratic countries (e.g. Zhir-
kov, Verkuyten and Weesie, 2014), few have compared
more similar countries. However, the cross-national re-
search that does exist, and the relatively limited number
of factors included in such studies, suggests that some dif-
ferences may exist in the relationship between different
risk factors and radicalization based on region (e.g. Ber-
ger, 2016; Gøtzsche-Astrup, 2021).
Regional differences in the effects of risk factors have
previously been understood by criminological perspec-
tives to be primarily the result of different social structures
and variance in opportunities (Akers, 1998; Gottfredson &
Hirschi, 1990). One theory that has elaborated extensively
on this relationship is Social Learning Theory, which
holds that social learning related factors are variably mod-
erated and mediated by a range of social structure factors
(Akers, 1998; Verrill, 2008). According to Akers (1998), the
general idea is that social structure encompasses:
«the general culture and structure of society and the particular
communities, groups, and other contexts of social interaction
provide learning environments in which the norms define what
is approved and disapproved, behavioral models are present,
and the reactions of other people (for example, in applying so-
cial sanctions) and the existence of other stimuli attach different
1We note at the outset that our approach is to identify what is com-
mon in Europe as compared to other regions, and we do not examine
variability within the European Union. While it is important to exam-
ine such variability, like other work in criminology there are currently
an insufficient number of studies for facilitating such an analysis (Far-
rington et al., 2019; Jugl, Lösel, Bender and King, 2021).
218 Michael Wolfowicz, David Weisburd und Badi Hasisi

reinforcing or punishing consequences to individuals’beha-
vior.« (p. 321).
Social structure variables can be grouped in different cate-
gories, both at the individual and macro levels, useful for
understanding and explaining differences in risk factor ef-
fects across contexts. At the macro level, the most impor-
tant factors are those associated with »differential social
organization«, which refers to differences in cultural, so-
cial, and demographic characteristics of societies. Impor-
tant factors related to »differential location in the social
structure«, may include the relative position of different
groupings, such as ethnic groups, within the social struc-
ture. Relatedly are factors associated with »social disorga-
nization«, theoretically defined structural variables such
as anomie, group-based inequality, and societal integra-
tion (Akers, 1998).
3 The systematic review and meta
analysis
We draw in our analyses from our Campbell field-wide re-
view of risk and protective factors for radicalization in de-
mocratic countries (Wolfowicz et al., 2021). The review’s
primary objectives were to investigate what the risk and
protective factors for radicalization are, and to identify the
relative magnitude of their relationships with radicaliza-
tion outcomes. Given the diversity of the literature, espe-
cially with respect to definitions of radicalization, the re-
view pre-determined its inclusion and exclusion criteria in
a systematic review protocol (Wolfowicz, Litmanovitz,
Weisburd and Hasisi, 2020). These criteria are summarized
in the following sections.
3.1 Outcomes
In line with contemporary approaches towards (counter)
radicalization, the review sought to include studies that
assessed both cognitive and behavioral outcomes of radi-
calization. While there are a wide range of proxies that are
used in the literature to assess »radicalization«, the review
adopted the criteria of the outcomes from McCauley and
Moskalenko’s (2017) two-pyramid model (TPM) of radicali-
zation to guide the inclusion and exclusion of studies. Un-
like other models, the TPM is not a process model nor does
it posit any specific direction or relationship between cog-
nitive and behavioural radicalization. In fact, it is more of
a typological model than it is a theoretical model and is
therefore useful for the purposes of meta-analysis which
seek to combine studies examining comparable outcomes
(Wolfowicz et al., 2021). In line with the TPM, the review
sought to include studies whose outcomes met the criteria
set forth by the TPM for radical attitudes and intentions
(cognitions), as well as behaviors.
1. Radical attitudes: Justification/support for radical be-
haviours carried out in the name of a cause.
2. Radical intentions: Willingness/intentions towards en-
gagement in radical behaviours in the name of a
cause.
3. Radical behaviours: Actual involvement in violent ra-
dical behaviours in the name of a cause, including ter-
rorism.
In line with the TPM, radical behaviors included both
sub-terroristic forms of radical violence, as well as terror-
ism. The review included studies employing both vali-
dated and non-validated instruments to measure cognitive
radicalization, as well as measures of outcomes derived
from self‐reports, family reports, administrative reports
(e.g. government or law‐enforcement), practitioner/clini-
cal reports, and databases whose data was derived from
open‐sources.
3.2 Types of studies
The review was limited to quantitative studies of an obser-
vational nature, namely cross-sectional, longitudinal, and
case-control studies. For a study to have been included it
must have employed a design that enabled the calculation
of an effect size, either by including a direct comparison or
control group, or a single sample in which there was var-
iation on the dependent variable.
3.3 Risk and protective factors
The review included all individual level factors for which a
positive or negative correlation with the outcome of inter-
est could be established. The review included all factors
that are described in the literature under any of the follow-
ing categories:
–Social, economic and psychological factors
–Proximal and distal factors
–Push and pull factors
–Socio-demographic/background characteristic factors
–Attitudinal/subjective belief factors
–Psychological/personality trait factors
–Experiential factors
Does context matter? European-specific risk factors for radicalization 219

The review excludes all factors that were not measured at
the individual level, for example:
–Meso-level factors: Community level deprivation, po-
pulation density etc.
–Macro level factors: GDP, GINI etc.
–Time-series factors: The occurrence of specific events
(e.g. terror attacks), or rates of social phenomena (e.g.
crime rates).
Additionally, the review did not include experimentally
manipulated factors as combining these with non-mani-
pulated versions of the same factors would lead to metho-
dological inconsistencies.
3.4 Context
As with other systematic reviews of risk factors, the Camp-
bell review limited itself to specific types of countries/re-
gions (Higginson et al., 2018; Litmanovitz & Montgomery
2016; Murray et al. 2018; Shenderovich et al. 2016). The re-
view cross-referenced the Organisation for Economic Co-
operation and Development (OECD) countries with the De-
mocracy Index’s list of democratic countries. The result of
this approach led to an inclusion of all OECD countries with
the exception of Turkey, which the Democracy Index ranks
a »hybrid regime« rather than a democratic system. As
such, studies were eligible for inclusion when their sam-
ples included participants from the following countries:
Australia, Austria, Belgium, Canada, Chile, Columbia,
Czech Republic, Denmark Estonia, Finland, France, Ger-
many Greece Hungary, Iceland, Ireland, Israel, Italy, Ja-
pan, Korea, Latvia, Lithuania, Luxemburg, Mexico, Nether-
lands, New Zealand, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland, UK, and USA.
For the purposes of the current study, each included
study was coded as being either »European« or »Non-Eur-
opean«. Although there is significant heterogeneity within
these two groupings, there is also a significant degree of
commonality. In particular, previous research has found
that the countries that make up these groupings tend to
cluster with each other in terms of patterns of deviant out-
comes (Eisner, 2002; Junger-Tas, 2010). Moreover, pre-
vious meta-analytic research has found that these regio-
nal levels of aggregation are often more informative than
using continuous measures pertaining to socio-cultural or
socio-economic metrics (Fraguas et al., 2021; Pinquart &
Kauser, 2018; Gaffney, Farrington and Ttofi, 2019).
Figure 1: Number of samples per country
220 Michael Wolfowicz, David Weisburd und Badi Hasisi

Table 1: Universal factors between European and other democratic country studies
Factor r95 %CI Q I
2
N(k)
Radical attitudes
Marital status -.04*** -.06, -.02 12.80
ns
14.03 37105 (11)
SES -.04** -.06, -.01 244.65*** 89.37 110617 (27)
Age -.05** -.08, -.02 1307.75*** 96.56 151045 (46)
Education -.07** -.10, -.03 568.90*** 94.90 72528 (30)
Parent Involvement -.10*** -.15, -.06 121.47*** 90.94 26175 (12)
Institutional Trust -.17*** -.27, -.07 822.18*** 98.78 47485 (11)
Depression .00
ns
-.07, .07 87.27*** 89.69 9027 (10)
Immigrant .01
ns
-.02, .04 183.06*** 87.98 63157 (23)
Anxiety .04†-.00, .08 23.90* 70.71 10409 (8)
Religiosity .05 -.02, .11 504.99*** 96.44 30978 (19)
Worship attendance .06* .01, .11 103.10*** 88.36 16761 (13)
Exp. Violence .07*** .05, .10 97.78*** 84.66 65566 (16)
In-group identity .07*** .038, .11 344.11
ns
93.03 77618(25)
Exp. discrimination .08*** .06, .10 74.80*** 73.26 47670 (21)
Males .10*** .08, .12 631.10*** 91.29 176203 (56)
Significance quest .14*** .08, .21 19.60* 54.08 2165 (10)
Perc. discrimination .15*** .10, .19 73.87*** 90.52 20093 (8)
Political grievance .15*** .08, .21 52.62*** 86.70 7990 (8)
Anomia .19*** .14, .24 105.31*** 89.56 19938 (12)
Low Integration .20*** .15, .25 321.80*** 93.79 42783 (21)
Self-sacrifice .20*** .09, .30 24.59*** 79.66 1704 (6)
Authoritarianism .25*** .15, .35 1962.24*** 98.98 37313 (21)
Moral Neutralization .32*** .23, .40 1119.20*** 98.75 52498 (15)
Political extremism .37*** .22, .51 653.44*** 99.24 38745 (6)
Radical intentions
Education -.03
ns
-.08, .03 32.87** 66.54 5660 (12)
SES -.03
ns
-.09, .02 21.46* 53.40 3147 (11)
Age -.08** -.12, -.03 165.75*** 85.52 14650 (25)
Openness -.16*** -.23, -.09 85.77*** 89.51 8196 (10)
Uncertainty .05** .01, .08 4.51
ns
11.21 4104 (5)
Gender (Males) .10*** .06, .14 135.39*** 80.06 14806 (28)
Self-Esteem .20* .00 .38 41.31*** 87.90 1789 (6)
In-group identity .25*** .15, .34 212.59*** 93.41 6359 (15)
Moral neutralization .36*** .21, .50 60.39*** 88.41 1235 (8)
Anger .40*** .27, .51 153.71*** 92.84 3029 (12)
Commitment .43*** .31, .54 97.97*** 91.83 2545 (9)
Activist Intent .44*** .34, .53 336.24*** 94.94 5446 (18)
Radical attitudes .48*** .38, .56 184.01*** 94.02 5917 (12)
Radical behaviours
Marital status -.03
ns
-.07, .01 25.27*** 80.21 48138 (6)
Age -.10* -.21, .00 365.92*** 98.09 50738 (8)
Does context matter? European-specific risk factors for radicalization 221

4 The current study
In the current study we examine which factors show evi-
dence of differences in their relationship with radicaliza-
tion outcomes (attitudes, intentions and behaviours) be-
tween European and non-European studies. We first iden-
tified which of the factors examined in Wolfowicz et al
(2021) included at least two European and two non-Euro-
pean studies. We subsequently carried out moderator ana-
lysis to identify statistically significant between region
heterogeneity (p<.05).
4.1 Included studies
The samples in the included studies pertained to a rela-
tively limited number of local contexts. In the EU, while a
few samples included participants from multiple countries
(N=10), the largest number of samples were from Denmark
(N=17), Spain (N=15), and the UK (N=17), followed by the
Netherlands (N=12), Germany (N=11), Belgium (N=9), and
France (N=8). A small number of samples were from Swe-
den (N=5), Norway (N=4), Switzerland (N=4), and Poland
(N=2), while a single sample represented the countries of
Austria, Greece, Italy and Hungary. Overall, the countries
represented in these samples can at the least be said to be
representative of western Europe.
Fornon-Europeandemocraticcountries,themajorityof
the samples pertained to the U. S. (N=52). However, there
were also a number of samples from Canada (N=12)andAus-
tralia (N=4), as well as two samples from Israel and South
Korea.Another12samplesincludedparticipants from multi-
plecountries,whileothersincludedthosefrombothCanada
and the U. S. (N=3). Overall, these samples cover a list of
countries that can at least be said to be representative of the
Anglosphere of non-European democracies.
5 Results
As noted earlier the Campbell systematic review and me-
ta-analysis identified over 100 risk and protective factors
for the outcomes of radical attitudes (29 protective and 71
risk factors), intentions (8 protective and 37 risk factors)
and behaviors (7 protective and 26 risk factors). With re-
spect to the relationship between outcomes, the review
identified and analyzed radical attitudes as a risk factor
for both radical intentions and behaviors. However, the
current analysis was limited to those factors for which a
minimum of two European and two non-European effect
sizes were present. As such, the current analysis was lim-
ited to 26 factors pertaining to radical attitudes, 13 factors
pertaining to radical intentions, and 4 factors pertaining to
radical behaviors. These factors are highlighted in Table 1
where they appear in rank-order according to the magni-
tude of the estimates.
2
Moderator analysis identified that between-region
heterogeneity was absent for the majority of factors. For
the outcomes of radical attitudes, statistically significant
between-region heterogeneity (p<.05) was found for 6 fac-
tors, whereas for both the outcomes of radical intentions
and behaviours it was only found for one factor for each.
The results of the moderator analysis can be found below
in Table 2 and are arranged alphabetically.
With respect to the statistically significant factors for
radical attitudes, SOCIO-ECONOMIC STATUS had a very
small but statistically significant estimate for EU studies
but a non-significant estimate for non-EU countries. For
INSTITUTIONAL TRUST, whilst estimates for both EU and
non-EU studies were statistically significant, the size of
the estimates differed substantially, with a small estimate
for the EU studies, and a more robust, moderate estimate
for non-EU studies. With respect to PARENTAL INVOLVE-
MENT, although the estimates for both EU and non-EU
studies were small, the estimate for the EU studies was
significantly larger. Similar findings were made with re-
spect to GENDER, with estimates being exceptionally
small, although larger for EU studies. With respect to both
INTEGRATION and MORAL NEUTRALIZATIONS, the esti-
Factor r95 %CI Q I
2
N(k)
Unemployed .19*** .06, .31 647.22*** 99.07 54620 (7)
Gender (Males) .39** .10, .61 1887.18*** 99.68 13641 (7)
Effect sizes are rcorrelations with 95 % confidence intervals. Q is Cochran's Q statistics for heterogeneity with p-value from Chi2 test. I2 and
T2=heterogeneity statistics. N=Combined sample size, K=Number of effect sizes. ***<.001, **<.01, *<.05.
Table 1: (continued)
2For factors for which such analysis was not possible, please see the
original review (Wolfowicz et al., 2020a).
222 Michael Wolfowicz, David Weisburd und Badi Hasisi

Table 2: Moderator (re)analysis comparing EU and non-EU studies
Factor EU Other Q
between
Attitudes
Age -.04* (38) -.07
†
(8) .395 (.530)
Anomia .20*** (8) .15** (4) .616 (.433)
Anxiety .04
ns
(4) .04
ns
(4) .000 (.964)
Authoritarianism .27*** (15) .22 (6) .075 (.784)
Depression .01 (5) -.01 (5) .070 (.792)
Education -.06** (24) -.09** (6) .489 (.485)
Exp. Discrimination .07*** (15) .07* (5) .005 (.944)
Experienced violence .09*** (9) .04* (7) 2.892 (.089)
Gender .11*** (41) .07*** (15) 4.171 (.041)
Immigrant .01 (17) -.02 (6) .410 (.522)
In-group identity .07** (17) .10†(8) .181 (.671)
Institutional trust -.12* (9) -.43* (2) 8.435 (.004)
Integration .16*** (15) .30* (6) 7.434 (.006)
Marital status -.05** (10) -.02 (2) .573 (.449)
Moral neutralizations .26*** (11) .47*** (4) 4.75 (.029)
Parental involvement -.12*** (9) -.04†(3) 5.707 (.017)
Perc. Discrimination .16*** (6) .11* (2) .929 (.335)
Political extremism .38* (4) .36* (2) .020 (.888)
Political grievance .14*** (6) .16* (2) .039 (.843)
Religiosity -.01
ns
(10) .11* (9) 3.211 (.073)
Self-sacrifice .17*** (3) .12* (2) .550 (.458)
SES -.05***(23) .03
ns
(4) 5.047 (.025)
Significance quest .11†(4) .18*** (6) 1.481 (.224)
Worship attendance .07* (8) .06 (5) .029 (.866)
Intentions
Activist intent .55*** (6) .38*** (12) 3.695 (.055)
Age -.07†(15) -.09** (10) .106 (.744)
Anger .42*** (7) .35** (5) .390 (.533)
Commitment .54*** (3) .37*** (6) 3.070 (.080)
Education -.04 (7) -.01 (5) .321 (.571)
Gender (Males) .09** (16) .12*** (12) .428 (.513)
In-group identity .27*** (13) .16*** (2) 2.681 (.108)
Moral neutralization .29†(4) .42*** (4) .662 (.416)
Openness -.22** (5) -.12** (5) 1.172 (.229)
Radical attitudes .49*** (8) .45*** (4) .180 (.671)
Self-esteem .32**(4) .01
ns
(2) 8.015 (.005)
SES -.04 (9) .00 (2) .541 (.462)
Uncertainty .05 (2) .05* (3) .013 (.908)
Behaviours
Age -.19*** (2) -.07 (6) 2.023 (.155)
Gender (Males) .28†(3) .46†(4) .481 (.488)
Does context matter? European-specific risk factors for radicalization 223

mates for EU studies were both significantly smaller than
the more moderate estimates for non-EU studies.
With respect to the other outcomes, for radical inten-
tions the estimate for SELF-ESTEEM was significantly larger
for EU-based studies than non-EU studies. For the outcome
of radical behaviors, the estimate for UNEMPLOYMENT was
significantly larger for EU studies, with a borderline moder-
ate sized estimate being more than double the size of the
small estimate for the non-EU studies. The two EU studies
included one study from the Netherlands, and another from
the UK, both of which compared terrorism offenders with
general population samples (Table 2).
6 Discussion
The current study conducted a confirmatory meta-analysis
in order to identify which risk and protective factors for
radicalization may have universal effects, and which have
unique effects in Europe. The original systematic review
and meta-analysis included some 100 risk and protective
factors for outcomes of both cognitive and behavioral ra-
dicalizations. For most of these factors, included studies
were exclusively or primarily from the European region,
thereby precluding their inclusion in our cross-regional
analysis. But based on the factors that were included in
our analysis, it was identified that between-region hetero-
geneity exists for only a small number of factors. This
means, that similar to the broader literature on the gener-
alizability of risk and protective factors for criminological
outcomes, most factors may have essentially universal ef-
fects (Farrington et al., 2019). For radical attitudes these
include factors with relatively smaller effects, such as per-
ceptions and experiences of discrimination, and factors
with larger effects, such as anomia, authoritarianism and
political extremism. These are all factors which may be,
and are already being targeted by counter-radicalization
initiatives in democratic countries (Wolfowicz et al., 2021).
As the objective of our study was to identify which
factors may be more relevant in the European context, we
focus our discussion on these factors only. We exclude
from our discussion those socio-demographic variables for
which differences were found, since these differences are
likely to simply reflect differences in the distributions of
these characteristics in the different populations. In
focussing on only the more substantive factors, we dis-
cuss; 1) Parental involvement, 2) Self-esteem, and 3) Un-
employment as it relates to radical behaviours.
6.1 Parental involvement and radical
attitudes
Although not objectively large, relative to other protective
factors found in the review, there is a modest relationship
between parental involvement and radical attitudes. Par-
ental bonds have repeatedly been found to be a key pro-
tective factor for a range of criminal and criminal analo-
gous outcomes (Flanagan, Auty and Farrington, 2019). Ac-
cording to social control perspectives there are a number
of elements to parental bonds, the most important of
which are attachment and involvement. In addition, poor
parental relationships are believed to be central to the de-
velopment of low self-control (Gottfredson & Hirschi,
1990), a key universal factor for both criminal and radical
outcomes (Wolfowicz et al., 2021).
Changing social norms may serve to explain why the
strength of the relationship between parental involve-
ment and radicalization is stronger in Europe than other
democratic countries. For example, a recent study of de-
linquency in the Netherlands found that over the last 15
years there has been an apparent improvement in paren-
tal bonds (and parental involvement in particular), and
the increased presence of this important protective factor
is partially responsible for a sustained decrease in youth
criminal outcomes (van der Laan et al., 2021). Similar
findings have been made in other countries, such as Swe-
den, leading scholars to suggest that cultural shifts have
taken place in many parts of Europe that have led to this
increase. Perhaps most relevant to our findings, this in-
crease has been found to corresponded with a decrease in
positive attitudes towards crime and offending behaviors
(Svennson & Oberwittler, 2021).
Factor EU Other Q
between
Marital status -.04 (2) -.03 (2) .095 (.758)
Unemployment .29*** (2) .14
†
(5) 4.735 (.030)
Pooled estimates are rcorrelations. ***<.0001, **<.01, *<.05, Number of studies in brackets. Q
between
is Cochran’s Q statistic with p-values
from the associated Chi
2
test in brackets.
Table 2: (continued)
224 Michael Wolfowicz, David Weisburd und Badi Hasisi

In applying these findings to counter-radicalization,
already across Europe, policy-makers have recognized par-
ents and family as key figures in combatting radicalization.
However, current approaches that deal with parents and
families appear to be relegated to two areas: 1) Hotlines for
reporting of radicalized children, 2) Resources for receiving
support for how to counter radicalization. Current ap-
proaches therefore focus primarily on equipping parents
with counter-narrative tools and strategies (El-Amraoui &
Ducol, 2019; Ranstorp, Gustafsson, Hyllengren and Ahlin,
2016). But rather than being a mere vehicle for identifica-
tion, reporting or delivering of counter-narratives, Eur-
opean interventions may benefit from integrating methods
to strengthen parental bonds (Ranstorp et al., 2016). This
could potentially be done through encouraging parental in-
volvement in education activities (Speckhard, Shajkovci
and Ahmed, 2018). In this regard, counter-radicalization
may benefit from adopting the types of evidence-based par-
ent training strategies that have been shown to successfully
improve parental bonds and reduce the likelihood of a
range of criminal outcomes (Piquero et al., 2016).
6.2 Self-esteem and radical intentions
There are two opposing theories when it comes to the re-
lationship between self-esteem and criminal outcomes.
One theory posits that individuals with low self-esteem
may be drawn to crime because they believe that it will
enhance their self-esteem, in part by attracting acceptance
and respect of those around them (Slaby & Guerra, 1988).
The other theory posits that high self-esteem can spill over
into narcissism, and that threats to self-esteem may be re-
sponded to more defensively, and aggressively, by those
high in self-esteem (Baumeister, Smart and Boden, 1996;
Bushman & Baumeister, 1998).
Similar opposing views have been put forth with re-
spect to radicalization. One perspective holds that indivi-
duals with low self-esteem may seek out stronger connec-
tions to collectives who can provide a sense of identity,
and thereby improve self-esteem (Kruglanski et al., 2018).
Another view is that for those with a group-based identity
and high-self esteem, frustration of goals or threats to the
collective may be responded to defensively in order to
maintain or affirm self-esteem (McGregor, Hayes and Pre-
ntice, 2015). Alternatively, insecure forms of high self-es-
teem, in which self-esteem is high explicitly by low impli-
citly, may seek certainty in radical belief systems and
groups (Trip et al., 2019). In sum, the latter perspective
views high-self esteem as a risk factor for radicalization
when it is inflated, threatened, or unstable (Beelmann,
2020). Our results suggest that the overall nature of the
relationship between self-esteem and radicalization is in
line with this latter perspective.
The riskiness of self-esteem has already been noted in
the context of counter-radicalization interventions, and in
European contexts specifically. While there is some initial
experimental evidence that shows that interventions
aimed at improving self-esteem hold promise for reducing
the likelihood of radicalization, these may only work when
coupled with empathy training. These findings reflect the
potential for improved self-esteem in and of itself to in-
crease the likelihood of radicalization (Feddes, 2015;
Feddes, Mann and Doosje, 2015).
It has previously been found that there is significant
cross-regional heterogeneity in the relationship between
self-esteem and criminal outcomes (Mier & Ladny, 2018).
The results point to the possibility that these differences re-
flect the normative values placed on self-esteem in the dif-
ferent societies, or the degree to which individuals‹identi-
ties are group-based (Turner, 1975). Similar to the relation-
ship between self esteem and radicalization described
above, research has found that the focus of western coun-
tries on promoting self-esteem as a normative value may
inadvertently promoted narcissism; the type of inflated
self-esteem that can increase the risk for criminal and radi-
cal outcomes. In segments of society in which relative
standing is an important value, such as in Western Europe,
this potential may be elevated. In order for self-esteem to be
fostered in such a way so that it provides the psychological
benefits that it promises whilst avoiding such negative con-
sequences, parenting training may prove beneficial (Brum-
melman & Sedikides, 2020). Self-affirmation approaches
may be especially useful as well since self-esteem, when
threatened, can lead to radicalization as an expression of
self-affirmation (Bélanger, 2021; Williams, 2020).
6.3 Employment and radical behaviors
The role of employment and poverty as a cause of terror-
ism is arguably one of the most extensively researched hy-
potheses in the literature. Perhaps more important than
objective socio-economic related strain, unemployment
can serve as a source of grievance and be a source of a lack
of personal significance (e.g. Belanger et al., 2017, 2019;
Krulanski et al., 2018). Additionally, unemployment can
be accompanied by social strain, especially when the state
of unemployment status is perceived to be the result of
discrimination (Agnew, 2010, 2016). This may be espe-
cially important for minority groups, who figure promi-
nently in the samples analyzed in this study.
Does context matter? European-specific risk factors for radicalization 225

One potential explanation for the differences between
European and other democratic countries in the effects of
unemployment may pertain to the relative degree of eco-
nomic integration of minority groups (Meleagrou-Hitchens,
Hughes, Clifford, 2019). In this regard, even though unem-
ployment is generally higher in European countries than in
other democratic countries such as the US, Canada, and
Australia, unemployment gaps of specific groups, particu-
larly Muslims and immigrants is greater in Europe (OECD,
2021).
This explanation is in line with evidence from macro--
level economic models which have found that while there is
little to no relationship between population-level employ-
ment and terrorism, there is a positive relationship with
minority economic discrimination (Piazza, 2011) and rela-
tive deprivation (Varaine, 2020). In Europe in particular,
there is a strong relationship with individual and country
level unemployment and collective relative deprivation
(Meuleman et al., 2020). Relative deprivation among the un-
employed has been found to be associated with a range of
factors pertaining to mental health and wellbeing (Walker &
Mann, 1987). However, the strength of this effect is depen-
dent on the prevalence of unemployment in society. So too,
unemployment’s impact on other risk factors, such as insti-
tutional trust, is greater in Western European countries than
in the US, and this has been attributed in part to the differ-
ential rates of unemployment in these regions (Giustozzi &
Gangl, 2020).
Another way that employment can effect radicalization
is through its conditioning of social bonds and routine activ-
ities (LaFree & Miller, 2008; Windisch et al., 2016). Through
its impact on routine activities, employment limits the
amount of unstructured free time in which the individual
can potentially engage with deviant elements or behaviors
(Apel & Horney, 2017). As changes to routine activities also
effect changes in socialization patterns, employment can
foster changes in other attitudinal factors (Walters, 2016;
Wolfe, McLean, & Pratt, 2017) such as legitimacy (Fagan &
Tyler, 2005), and forms of perceived injustice and relative
deprivation (Burchardt, 2005; Folger & Kass, 2000; Agnew,
2010, 2016; Rice, 2009).
In countries like the UK and Netherlands, providing
at-risk groups with employment is part of primary and sec-
ondary level counter-radicalization. However, the ratio-
nale behind the inclusion of employment is that socio-eco-
nomic factors, and a lack of social integration are the pri-
mary risk factors for radicalization (Van Dongen, 2016;
Vidino & Brandon, 2012 b, 2012 a; Thornton & Bouhana,
2017; HM Government, 2018). Some have previously criti-
cized this view as undermining the potential benefits of
employment by focusing on factors that are known to
sometimes increase a sense of marginalization (Van Don-
gen, 2016).
In contrast to this perspective, countries such as Aus-
tralia (Cherney, 2016) and the U. S. (National Academy of
Science, 2017) treat employment more as a form of situa-
tional prevention. In line with the routine activities and
social bonds perspectives, employment is more of a diver-
sionary approach, and can serve as an off-ramp for pro-
moting disengagement from radical trajectories (Simi et
al., 2016). According to this perspective, while any effect
on radical attitudes is desirable, this is not the purpose of
employment, and nor is de-radicalization necessary for
secondary and tertiary level interventions to succeed in
promoting abstention or desistance from radical beha-
viours (Bartlett et al., 2010; Kruglanski et al., 2018). Given
that the effects of unemployment are larger in Europe than
in other democratic countries, European countries may
benefit from adopting and integrating this view of employ-
ment into their counter-radicalization approaches. As Day
and Kleinmann (2017) describe it:
»We need to make employment a national security priority. We
need to rethink »assimilation« to be less about mainstreaming
cultural identity, and instead think about networks of would-be-r-
adicals being absorbed and supported by healthcare, education,
democratic representation, and respect for their beliefs. We need
affective bonds that are stronger than theirs. Real CVE is about a
stronger civic life, not merely »countering narratives.« (p. 21).
7 Limitations
While our study is the first to compare and contrast the
magnitude of the effects for risk factors for radicalization,
there are a number of limitations, both in terms of the
data, the methodology, and interpretation. In terms of the
data, as noted in the original review (Wolfowicz et al.,
2021), there is little in terms of longitudinal study, mean-
ing that the current estimates represent putative risk and
protectives rather than risk factors. This means that we
cannot make any claims about the causality of such fac-
tors as they pertain to radicalization. Methodologically,
meta-analysis is limited to the availability of data. This
means that we were limited by the number of studies
available for each factor which prohibited looking at
cross-national effects (Farrington et al., 2019). This is im-
portant as there still exists a significant degree of hetero-
geneity between the different European societies (Kaasa,
Vadi and Varblane, 2014). And when it comes to radicali-
zation, and possible variation in the effects of risk factors,
there is even evidence of within-region differences (Ellis et
al., 2021), and more local-level differences (Miconi et al.,
226 Michael Wolfowicz, David Weisburd und Badi Hasisi

2020). As more research becomes available it may even-
tually be possible to carry cross-national analyses with a
finer grain of analysis (Jugl et al., 2021).
With regards to interpretation, there is a potentially un-
limited number of avenues for exploring societal and cul-
tural differences that may explain the nature of the effects
(Rutter, 1999). Such factors may include indices relating to
societal individualism, power-dominance orientation, and
masculinity. While the current study was focused on cross-
regional effects, these types of cross-cultural factors are de-
serving of specific attention in future research.
8 Conclusions
With the proliferation of counter-radicalization interven-
tions in the west in recent years, there has been a debate
as to the degree to which countries should target ›univer-
sal‹factors or contextually specific factors. Concurrently,
there has been little evidence upon which identification of
universal and context specific factors can be made. We
found that for the overwhelming majority of factors for
which evidence exists from different democratic regions,
there is no significant inter-regional heterogeneity. That
is, the current evidence points to these factors as having
›universal‹relationships with radicalization in democratic
countries. These include many factors already targeted by
counter-radicalization interventions, such as: In-group
identities, Experiences of discrimination, Perceived discri-
mination, and Anomic conditions (e.g. Social alienation).
Additionally, for other individual background characteris-
tics, including socio-demographic factors, personality re-
lated factors (e.g. Openness, Authoritarianism/Funda-
mentalism), current evidence suggests that they too have
universal effects. As such, for interventions that target
such factors, context may not matter. This means that it
may also be realistic to draw lessons from other countries‹
approaches and experiences in the targeting of such fac-
tors. However, we also found evidence to support claims
that certain factors may have context specific effects. In
this regard we found a small number of risk factors whose
relationship with radicalization was significantly larger in
EU countries than in other democratic countries and vice
versa. For these factors, context does appear to matter.
It is interesting to note that two of the factors that are
commonly targeted by European interventions, namely in-
tegration and institutional trust, have relatively small
(though significant) relationships with radicalization more
generally in the Campbell review, but these relationships
are even smaller in the European context. This raises con-
cerns about the potential effectiveness of European inter-
ventions that focus on such factors. Whilst these factors
shouldn’t necessarily be discounted, if anything it is non-E-
uropean democracies that should consider focusing on in-
tegration in the context of counter-radicalization strategies.
With regard to employment we found the employment was
much more important in the European context, suggesting
that employment-oriented interventions may be useful.
The results of this study indicate that while context
rarely matters when it comes to risk factors for radicaliza-
tion in democratic countries, sometimes it does. Unfortu-
nately, counter-radicalization policies are often »shaped
less by evidence-based research, and more so by local poli-
tics, history and culture« (Hardy, 2018:100). The results of
this study indicate that European countries may benefit
from dedicating greater resources to interventions and po-
licies that target factors for which evidence exists that could
identify them as context specific. These factors include both
universal and specific risk factors in the European context.
Funding: Funding was received from EU grant no. 699824
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