When reflecting on this book’s insights, a key question is highlighted: What is the prospect for effectively preventing and resolving armed intrastate conflicts globally? The threat of such conflict erupting remains a constant risk for policy-makers and researchers to investigate, and to prepare for constructive intervention. As discussed throughout this text, the challenges inherent to establishing effective peacekeeping policies and resolving intrastate conflict remain. Furthermore, this chapter addresses how areas of non-violent conflict, but high tension, threaten to escalate in the future. Is it possible to successfully intervene and to deescalate future intrastate violence? From the timing of intervention to international cooperation, the debates and critical lessons that we conclude with here will encourage thought-provoking discussions on formulating effective policies to prevent and end intrastate violence.

Recent years have witnessed the rise of a range of authoritarian populist, illiberal, far-right, nativist, and extremist parties. We have seen democratic structures threatened or incrementally dismantled through the subversion of an established democratic party by an outsider or ascendance of the extremist wing of a right-wing party. Parties and party leaders occupying an ill-defined space on the political spectrum today generally present a much greater threat to democratic governance than overtly antidemocratic fringe outfits. The ambiguity of such parties, their growing size, their entry into government, the subversion of “good” democratic parties by a “bad” leadership, and the rise of the “shadow party” mean that contemporary political party threats seriously frustrate the possibility of remedial action afforded by existing public law and policy mechanisms. They also require us to reflect anew on crafting novel remedies and to revisit our assumptions about parties as creatures of central constitutional importance.

This chapter argues that throughout history many religions have proved themselves capable of sparking and fueling hostility toward outsiders and even toward people in the same faith who are viewed as unacceptable for one reason or another. We examine recent manifestations of extremism in Christianity, Hinduism, Buddhism, Judaism, and Islam, explaining that analysts often disagree about the extent to which religious beliefs and institutions are causally important. Key terms such as religious extremism, fundamentalism, radicalization, and terrorism are defined, noting the crucial importance of maintaining a distinction between the religious extremist and the extremely religious. Though we suggest researchers face many methodological challenges, we explore a broad range of empirical studies on related topics. The chapter also reviews theory and research on why and how people become religious extremists. We further draw on the psychology of radicalization, arguing that nowadays most scholars believe that there are cognitive and behavioral processes at work. Some people may move directly to carrying out terrorist deeds without acquiring much group ideology or religious belief.

Extremism of all types arises from a motivational imbalance wherein one need outweighs all other needs. When such a process occurs, more means to achieving the focal goal, including those considered extreme, become available to the individual. Presently, we focus on the need for significance, an existential social need. When the quest for significance is dominant, an individual may be willing to make extreme sacrifices in order to achieve their goal. The quest for significance can be activated through many different means, one of which is the loss of significance through exclusion. When one perceives that they have been excluded, their motivation to regain respect is activated. When this motivation to restore significance comes to suppress one’s other needs, the individual becomes willing to engage in activities they may have previously considered socially unacceptable, including joining extreme groups and participating in violence, in order to fulfill their quest for significance.

Feeling marginalized, silenced and excluded, as an individual or as a (sub)group within a collective, can make one feel uncertain about one’s self and identity and about “fitting in.” This feeling of uncertainty can be reduced by group identification – especially with a distinctive group that has a clearly defined, unambiguous, and homogenous social identity. Such groups and identities can sometimes be characterized as extremist. Excluded individuals may exit the larger group to identify with a different and possibly more extreme group, and the larger group may thus become less diverse and more homogeneous and extreme itself. Members of excluded subgroups can bond tightly together as a highly distinctive entity and identify strongly with it, a process that can fragment and polarize the larger group into oppositional or combative factions. In this chapter we draw upon an uncertainty identity theory framework to describe how exclusion can generate self and identity uncertainty, which is resolved by a process of identification that fragments groups and can produce extremist groups and identities.

The theoretical models propose that chronic social exclusion inevitably leads individuals into a state of psychological resignation and behavioral withdrawal. After reviewing the literature addressing chronic exclusion among general and marginalized populations, we propose that the chronic exclusion–resignation link might not be inevitable and that chronically excluded individuals remain sensitive to novel social affiliations. From here, we discuss how chronic exclusion and the resignation stage can sensitize individuals to the early stages of the radicalization process. We propose that the indomitable need for affiliation may drive chronically excluded individuals toward social resurrection when supported by prosocial sources of reconnection. However, without such avenues, radicalization may become an appealing path for reaffiliation, leading to extremist groups. This chapter elucidates the complex interplay between chronic exclusion, resignation, and radicalization, and it might inform the development of targeted strategies fostering social reintegration and preventing the allure of extremist ideologies among chronically excluded individuals.

Being left out by others is a painful experience that threatens basic needs. When people are excluded, they may merely distance themselves from those who have wronged them to avoid further rejection. However, some individuals may engage in compensatory actions to defend their self, their group, or the interplay between them in a way that could be a first step for radicalization leading to violence. How and when people opt for each strategy might vary depending on psychosocial mechanisms as well was macro-level cultural differences. Here, we focus on a mechanism useful for capturing who is more willing to fight or flee under social exclusion – identity fusion, a profound alignment between the personal self and a group, individual, value, or ideological conviction – and on a global cultural factor of relevance for the link between exclusion and extremism, as it is the distinction between WEIRD and non-WEIRD populations.

Can the experience of being ostracized – ignored and excluded – lead to people being more open to extremism? In this chapter we review the theoretical basis and experimental evidence for such a connection. According to the temporal need-threat model (Williams, 2009), ostracism is a painful experience that threatens fundamental social needs. Extreme groups have the potential to be powerful sources of inclusion and could therefore address these needs, thereby making them especially attractive to recent targets of ostracism. We also identify a set of factors that is theoretically likely to affect this link and review evidence for the opposite causal path: People are especially likely to ostracize others who belong to extreme groups. Together, this suggests a possible negative cycle in which ostracism may push people toward extreme groups, on which they become more reliant as social contacts outside the group further ostracize them.

Political extremists want to redefine and narrow who belongs and who does not in a society, often by trying to push groups such as immigrants, other ethnic groups, races, or religions out. This is what far-right extremists try to do. Redefinition can also mean trying to pull one’s own group out of society. This is what radical Islamists in Western societies try to do. Extremists of whatever variety have a common interest in fracturing the public sphere where broad-scale public deliberation is engaged. Non-deliberative approaches to extremism include bans and restrictions on extremist expression and consensus institutional designs to induce moderation. After noting their limitations, Chapter 5 turns to deliberative responses, beginning with the (limited) prospects for direct engagement with extremists. A multilayered approach involves starting with possibilities for reaching those who might be attracted to extremism (but also be attracted to other possibilities), deploying discursive psychology in the interests of building bridges. This approach then moves on to contemplation of the role that designed deliberative forums might play and finishes with a look at how performances by political leaders can try to set terms of discourse in the public sphere that can negate extremist appeals.