One of the big surprises since the end of the Cold War has been the growth of radical Islamist groups, especially those that adhere to Salafi jihadism, an ultraconservative reform movement that seeks to establish a transnational caliphate based on sharia law. These organizations reject democracy and believe violence and terrorism are justified in pursuit of their goals. Before 1990, there was only a handful of active Salafi jihadist groups. By 2013, there were 49.

The proliferation of these groups is puzzling because their goals are far more radical than those of the Sunni population they seek to represent. According to a 2013 survey of 38,000 Muslims in 39 countries conducted by the Pew Research Center, most Sunnis favor democracy over autocracy and large majorities strongly reject violence in the name of Islam. If so many Muslims disagree with the goals and methods of these radical groups, why have they multiplied?  

The answer has little to do with religion or ideology and everything to do with politics and security. In environments characterized by rapid political change, limited rule of law, and endemic corruption, moderate citizens have rational reasons to favor ideologically extreme groups. This is true in any country, Muslim or not. And it is true even if most citizens do not believe in the underlying goals and ideology of such movements. The rise of radical Islamism is not the result of increased support for extreme ideas but the result of average Sunnis behaving strategically during turbulent times.


When civil wars break out, as they have in Chad, Iraq, Libya, Nigeria, Mali, Pakistan, Somalia, Syria, and Yemen, moderate citizens have two options: either pick a side or attempt to remain neutral. The best choice is to align with the armed faction most likely to win the war and institute real political reform. Backing the victor protects an individual from postwar reprisals, and siding with a group that promises reform opens up the possibility of positive political change. But citizens do not know who will come out on top or how the winner will behave once in power.

This strategic situation gives extremist groups an advantage. An extreme ideology allows a group to recruit zealots, who are willing to fight longer and harder for victory than moderates. These dogged fighters help the group win early battles and build a reputation for discipline and effectiveness. The result is a type of tipping game: true believers join first because of their unwavering dedication to the cause; then more practical individuals join because they believe the group is likely to win. This is exactly what the terrorism expert Will McCants believes happened in Syria: the early success of the Islamic State (or ISIS) convinced many former fighters of the Free Syrian Army to defect to what they felt was the better-funded and more organized jihadist group.    

Moderate citizens would also prefer to back the faction that is most likely to remain uncorrupted once in office. Determining who will govern justly, however, is extremely difficult. Rebel leaders have incentives to claim that they are different from incumbent elites and desire political change, even if they are really motivated by ambition or greed. In countries with few institutional checks on executive power, selling out once in office is common.

Individuals do not need to believe in a radical interpretation of Islam to support an extremist group.

Once again, an extreme ideology gives groups a leg up. First, hard-liners are expected to reject mediocre deals more often than moderates, forcing governments to make better offers. This is why, for example, the Palestinians might prefer Hamas over the Palestinian Authority when it comes to negotiating with Israel. Second, embracing an extreme ideology suggests that a rebel leader is interested in more than just power or enrichment. This is especially true if an ideology demands costly personal sacrifice from its leaders such as abstinence or poverty. Osama bin Laden was able to signal his commitment to more principled rule because everyone knew he had given up his fortune to fight. Finally, religious extremist groups often have their own justice systems, which creates an additional check on bad behavior. Islamist extremism, for example, comes with its own extensive jurisprudence. The leadership of al Qaeda appeared to understand this advantage when it targeted regions where local populations needed basic governance. In religious communities, there are also trustworthy third parties, such as imams, muftis, and ayatollahs, who can step in to arbitrate disputes and punish leaders who abuse their power.


Individuals do not need to believe in a radical interpretation of Islam to support an extremist group. This has significant implications for U.S. counterterrorism strategy. Dissuading true believers from joining these movements is extremely difficult, but convincing moderates to defect might not be. 

The best way to undercut moderate support for organizations such as al Qaeda and ISIS is to encourage political settlements to the civil wars that sustain and harbor these groups. Political settlements are the kryptonite of Salafi jihadism. Power-sharing agreements end violent political contestation. For moderates, this means that the choice is no longer which group to back but whether to accept a role in government or continue fighting. The best option is clear. And once moderates gain political representation, the base of support for extremist groups declines. This is exactly what happened to the many paramilitary groups in Northern Ireland after the signing of the 1998 Good Friday Agreement. Today most of Northern Ireland’s radical groups have disarmed and violence has dramatically declined. It should come as no surprise, therefore, that ISIS warned Iraqi Sunnis to stay away from the polls in May 2018, stating that “the voting centers and those within them are targets of our swords.” The group wasn’t afraid of losing the true believers. It was afraid of losing the moderates.     

The United States should also help governments in conflict zones develop stronger constraints on executive power. The lack of checks on Arab leaders and the extraordinary corruption that has characterized these regimes for decades means that most Sunnis simply do not believe that moderate leaders will not sell out once in power. It is no coincidence that an ideology that emphasizes morality and justice has emerged in a region that has been dominated by repressive and shockingly bad governments. Investments in the rule of law and stronger checks and balances would negate the need for a secondary system of justice and undercut one of the reasons moderates support extreme groups. Of course this is easier said than done. Still, the United States has historically had some success in encouraging allies such as South Korea and Taiwan to make democratic reforms. The stronger the rule of law, the less appealing extremism is likely to be.

Another way to undercut extremist groups is to counter their propaganda. Salafi jihadists have convinced at least some moderates that they are more likely to institute a just political system than their opponents. One way to combat this narrative is to publicize the many instances in which leaders have been caught deviating from the rules and principles that they preach. A classic example is the July 2014 video of ISIS leader Abu Bakr al-Baghdadi wearing a Rolex watch while calling on believers to wage jihad in Iraq. The United States can also encourage moderate religious authorities (often tribal leaders) to contest the legitimacy of radical leaders who attempt to use their religiosity to their advantage. This is exactly what happened during the Anbar Awakening, when the United States worked with tribal leaders against Al Qaeda in Iraq.

An extremist ideology will always attract some true believers, but during times of uncertainty and insecurity it will attract moderates as well. If the United States can change the conditions that make supporting these groups a rational choice for average citizens, it will be much more difficult for extremism to thrive.

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  • BARBARA F. WALTER is Professor of Political Science at the University of California–San Diego’s School of Global Policy and Strategy.
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