Violent extremists killed more than 20,000 people in 2019 alone. Although most people are horrified when they hear about these groups' heinous atrocities, at least a few are inspired instead, and they seek out ways to join these violent groups and act on their behalf.

According to the Global Terrorism Database, more than 900,000 perpetrators were responsible for directly carrying out over 200,000 terrorist attacks between 1970-2019. That's not even counting people who indirectly or anonymously helped the groups plan their attacks. What these groups do is wrong, so how can they be so successful at recruiting people to their cause? My colleagues and I designed a study to try to find out.

Morally Motivated Terrorists

When you hear news of violent extremist groups killing and injuring people, you might just assume that the members of these groups lack a moral compass. After all, they seem to have a clear disregard for what most people think is right or wrong. However, a growing body of research suggests that violent extremists actually believe their harmful actions are morally righteous. That is, they believe their violent means serve some virtuous end.

What moral ends could be so important that perpetrators are willing to harm others in pursuit of them? The short answer is that the moral priorities driving terrorists appear to be the same moral values that drive everyone else. That is, people around the world are concerned about caring for vulnerable others, fairness and justice, loyalty to one's community, respect for authorities and tradition, and desires for purity or sanctity.

Given research suggesting that violent groups think what they are doing is morally right, we wondered whether this moral justification process was key to understanding how they recruit others to their causes, too. After all, I might have an easier time convincing you to join my cause if you believe what I am doing is morally good. And, if I can attach my cause to moral attitudes you already hold, you might be more willing to act on behalf of my cause.

How Terror Groups Exploit People's Moral Values

To find out how violent groups leverage people's moral concerns, we investigated propaganda that was created by known terrorist organizations. In total, we collected 873 propaganda items created between 1920–2018 by 73 terrorist groups that have committed violence in the United States. We carefully analyzed their propaganda, looking for themes and patterns that relate to common moral values. Then, we tried to link those moral themes in terrorist propaganda to how many violent attacks and casualties the terror groups were responsible for.

First, we found that propaganda items often conveyed moral themes—95.88% of them emphasized at least one moral value. But which moral values terrorists emphasized in their propaganda largely matched the moral concerns most important to non-extremists of the same ideologies. For instance, just as left-wing non-extremists tend to prioritize fairness in their morality, left-wing terrorist groups also tend to emphasize fairness concerns in their propaganda. And just as politically right-wing non-extremists tend to prioritize loyalty in their morality, right-wing terrorist groups also emphasize loyalty. So, if we know the terror group's ideology, we can predict with some accuracy how they will attempt to recruit outsiders to their cause. Nevertheless, we also found that appeals to loyalty and fairness were emphasized across all propaganda, regardless of terrorists' ideologies.

Finally, one moral theme was especially revealing of a terrorist group's violent activity. The more a group emphasized purity as a moral virtue in their propaganda, the more that group tended to attack others and the greater the number of casualties they caused globally and in the U.S. To a lesser extent, the more a terror group emphasized loyalty to the group in their propaganda, the more U.S. casualties they caused as well.

Big Picture

We tried to be comprehensive, but we can't claim to have the final word on terrorist propaganda. First, we only examined terror groups who have acted violently in the U.S. We can't easily assume that groups acting in other parts of the world use the same recruitment strategies. Second, even though we could tie moral themes in a group's propaganda to their violent activity, we can't say for sure what's causing what. These violent attacks are the product of a complicated slew of factors that go beyond simple moral principles.

Nevertheless, our study highlights that violent extremists attempt to persuade otherwise decent people to join and fight on behalf of their cause by exploiting their moral values. The scary thing is that these are pretty much the same tactics used in more mundane sorts of persuasion. Moral arguments show up in all kinds of messages that can sway people's views. Although the effects of violent extremism are horrendous, their origins might be more familiar than you realize.

For Further Reading

Hahn, L., Schibler, K., Lattimer, T., Toh, Z., Vuich, A., Velho, R., Kryston, K., O'Leary, J., & Chen, S. (2023). Why we fight: Investigating the moral appeals in terrorist propaganda, their predictors, and their association with attack severity. Journal of Communication, Advance online publication.

Fiske, A. P., & Rai, T. S. (2015). Virtuous violence: Hurting and killing to create, sustain, end, and honor social relationships. Cambridge University Press.

Kruglanski, A. W., Szumowska, E., Kopetz, C. H., Vallerand, R. J., & Pierro, A. (2021). On the psychology of extremism: How motivational imbalance breeds intemperance. Psychological Review, 128(2), 264–289.

Skitka, L. J., & Morgan, G. S. (2014). The social and political implications of moral conviction. Political Psychology, 35, 95–110.

Lindsay Hahn is an Assistant Professor in the Department of Communication and Center for Cognitive Science at the University at Buffalo, SUNY where she directs the Media Psychology and Morality Lab. Her research investigates morally laden media, its uses, and its effects on audiences across the lifespan.