“The process and structure of radicalization and extremism,” J.M. Berger, a fellow with the International Centre for Counter-Terrorism in The Hague, wrote via email, “are the same in different kinds of movements, even when the content of the extremist belief is different (such as with neo-Nazis and jihadists).”I feel doubts because to some extent all politics works this way; don't Democrats and Republicans identify enemies they claim are making them suffer? Doesn't the language of crisis and solution permeate every political campaign?
Scholars have often observed a radicalization process that goes something like this: After a first contact with the ideology, a person’s curiosity drives them to seek out more information, often through social media. After trying it on for size, they decide that the ideology sufficiently addresses their grievances, usually by framing it as the result of their group—their Muslim brothers and sisters, or their brothers and sisters in the white race—are being victimized by another group, say infidels or non-white immigrants. Then, the new adherent will consider whether he or she is doing enough to advance the cause, and if the answer is no, the person will act. “Extremist groups rely on a crisis-solution construct,” says Berger. “The in-group”—the ideological group, say, neo-Nazis or ISIS members—“is afflicted with a crisis that is blamed on the out-group”—people excluded from that group as enemies and threats, say, non-believers or non-whites—“and the extremist movement is presented as offering a solution to that crisis, which is often violent. The crisis is defined as being intrinsic to the identity groups involved, rather being than situational or temporary.” . . .
Violence isn’t always the result; few people radicalize in the first place, and still fewer commit attacks after doing so. But what can lead to violence is the many ways in which the process of radicalization is constricting: It alienates you from family and friends, and posits an acute problem to which the ideology demands a solution. After a while, it feels like an emergency every day. “The general psychological process of moving to those movements is very much the same,” says Koehler, who is also a senior fellow at George Washington University’s Program on Extremism. “It is a process of de-pluralization and isolation. There is a grievance or perceived threat, and it gets more and more intense until you don’t see any other solution but violence.”
I don't see how this account usefully discriminates between people who become socialists or join the Moral Majority from those who become suicide bombers.
I have likewise seen definitions of a "cult" that seem to describe all organized religion.
Movements are extremist because they are extreme, not because they are like all other movements. And what makes them extreme is not at all touched by this definition.