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Illustration by Matt Chase

The Threat Comes Home

By July 2014, the Islamic State had conquered vast areas of Iraq and Syria, and the group’s leader, Abu Bakr al-Baghdadi, declared the establishment of its caliphate. Strong and confident, the group’s leadership appealed to jihadists from around the world to come fight and to bring their skills and talents to help govern and provide services. Tens of thousands of jihadists from around the globe responded to the call. 

While the Islamic State is far from defeated today, the U.S.-led coalition ejected the group from a vast majority of the of the territory it once controlled. Even before the coalition campaign against the Islamic State began in August 2014, the threat foreign fighters would pose when returning home was readily discussed. 

At the 2014 Overseas Security Advisory Council (OSAC) Annual Briefing, then-U.S. Secretary of Homeland Security Jeh Johnson spoke about the dire threat that returning foreign fighters presented domestically and abroad.

Despite these dire warnings, the foreign fighter threat has not materialized as feared. To be clear, foreign fighters still pose a persistent threat, but it is a manageable one—not the catastrophe that was feared—due to three main factors that are mitigating the threat.  


Perhaps the most important of these factors is the recognition that the threat exists, and the massive effort that governments in the West have put into combating it. This is in stark contrast to the environment that existed in 1992–1993 when foreign fighters who left Afghanistan began to attack U.S. interests. 

Investigators of the December 1992 bombings directed against U.S. military personnel in Aden, Yemen, and the January 1993 rocket attack against the U.S. embassy in Sana, Yemen, originally thought that Libyans were responsible. However, the investigation revealed that the attacks were conducted with specific techniques taught by the CIA’s Office of Technical Services to foreign fighters in Afghanistan, enabling investigators—including the author—to determine that the tactics were brought back to Yemen by fighters who were previously in Afghanistan. 

After the February 1993 World Trade Center bombing, investigators from the New York Police Department and the U.S. Bureau of Alcohol, Tobacco, Firearms, and Explosives located a piece of the demolished truck with a vehicle identification number—which helped them track down the individuals who rented the truck used in the bombing.

It quickly became evident that many of the men in the group that had organized the attack had connections to Afghanistan. Investigators, including the author, eventually discovered that two of the bomb makers were dispatched to New York from Afghanistan. But it would still be some time before investigators recognized that the Yemen attacks and the World Trade Center attack were conducted by the same organization—al Qaeda. 

These events helped raise awareness in the U.S. government and its allies about the threat posed by the tens of thousands of foreign fighters who had trained and fought in Afghanistan. They also previewed the subsequent waves of jihadists who flocked to battle zones like Bosnia (1992–1995) and Chechnya (1994–1996).

Despite some awareness of these potential threats, however, reaction was somewhat muted in the pre-9/11 world. Consider the case of Sergeant Ali Mohamed, who was convicted for his role in the bombing of two U.S. embassies in 1989. While stationed at Fort Bragg in North Carolina, Mohamed told his Army supervisor that he was taking leave to travel to Afghanistan to fight with the mujahideen. 

Awareness increased after the 9/11 attacks and a string of failed or foiled terror attacks. For instance, Jose Padilla, who was arrested in 2002 for plotting a bomb attack, had been sent to the United States by al Qaeda. Adnan Shukrijumah, a senior al Qaeda member who grew up in south Florida, was tracked for years before he was killed in Pakistan in 2014. And consider Abdulhakim Mujahid Muhammad’s attack in Little Rock, Arkansas, in 2009. He was trained by al Qaeda in the Arabian Peninsula in Yemen. There was also the failed May 2010 Times Square bombing by Faisal Shahzad, who received bomb-making instruction from the Pakistani Taliban during a trip to Waziristan. 

Each case highlights the world’s elevated awareness of the threat posed by returning foreign fighters in the years since 9/11, causing the U.S. government and its global counterparts to focus significant effort into identifying and tracking jihadists who left home to travel abroad to train or fight.


Another strong mitigating factor is ideology. While tens of thousands of Muslims have fought in the various theaters of jihad since the 1970s, only a very small percentage returned to their countries of origin to conduct terrorist attacks. Some Muslims may feel compelled to travel to places like Syria to fight to defend fellow Muslims, but many of those who do so are not jihadists. 

Furthermore, there are also differences among those who hold jihadist beliefs. For example, some jihadists believe it is religiously permissible to travel to a place such as Syria or Iraq to fight for Muslims who are being oppressed or attacked (defensive jihad) or who they see as being locked in an internal sectarian fight. But these same jihadists do not believe it is permissible to conduct terrorist attacks against civilians outside of theaters of war. 

These people have no qualms about killing armed combatants in a war zone, but they believe that Islam clearly prohibits attacks against noncombatants. Others believe it is not permissible to conduct attacks in countries that have provided them refuge.

Jihadist infighting has also proved to be a significant ideological arrestor. First, the more divided the jihadists are and the more they fight among themselves, the less attention and resources they can spare to conduct attacks in areas beyond their war zone. Second, some foreigners who traveled to Syria, Somalia, and Yemen abandoned jihadism after becoming disillusioned by internal ideological squabbling. Infighting has also increased the number of jihadist deaths, and many foreign fighters—including high-profile foreigners like Omar Hammami in Somalia—were executed by members of the group they traveled to join. 


Finally, it is important to note that most of the jihadists traveling overseas are provided training, but that training is more like a paramilitary boot camp. They undergo physical fitness training and are taught to fire rifles, throw grenades, and move as part of a fire team. 

These skills are useful on the battlefield in places like Libya and Syria, but the operational environment is quite different in cities like New York or London. The skills to plan and conduct terrorist operations in a hostile environment—terrorist tradecraft such as surveillance, clandestine communications, operational security, weapons acquisition, and bomb making—are far more akin to the skills of an intelligence officer than an infantry soldier.

Due to this lack of terrorist tradecraft capability, many foreign fighters have been detected and arrested before they could launch attacks. Occasionally a single returnee slips through the system, like the suicide bomber who struck Manchester, England, in May 2017, but it is not the norm. 

It is even rarer for an entire cell of attackers to escape detection, like the group behind the November 2015 Paris attack and March 2016 Brussels airport bombing. However, they are the exception rather than the rule. 

Since the declaration of the Islamic State, far more attacks were conducted in the West by homegrown jihadists than returning foreign fighters. Examples of homegrown jihadist attacks in the United States include the December 2015 San Bernardino shooting, the June 2016 Pulse nightclub attack, and the October 2017 vehicular assault in New York City. 

All that said, however, the threat of foreign fighters remains. It is important to recognize that like any other would-be assailant, foreign fighters remain bound to the constraints of the attack planning cycle and are vulnerable to detection as they progress through that process.

While relatively simple attacks such as armed assaults, knife attacks, or vehicular assaults require less planning and preparation than a car bomb attack, they nevertheless require the attacker to conduct activities—such as pre-operational surveillance of potential targets—that can be detected if someone is looking for them. 

Government security forces, private security, and the citizenship at large must remain cognizant of the threat and stay alert for signs of attack planning in progress. Given that most security programs have a limited number of personnel, programs to train employees to spot signs of attack preparation are also critically important. 

“See Something, Say Something” works, and a trained and vigilant workforce serves as a significant force multiplier for security departments.

In addition, corporate security directors must plan for the worst and develop and test contingency plans. They need to train their workforce to help mitigate the impact of an attack directed at their facilities and personnel. However, it is always better to prevent an attack than respond to one.  

What Is Jihad?

The word "jihad" in Arabic can mean to "struggle" or "strive for" something. It can be used in reference to either an internal or external struggle. When used in the external sense, the word is often applied to an armed struggle. A person engaged in a struggle is a mujahid (mujahideen when plural). A militant Islamist who seeks to establish an Islamic polity through an armed struggle (jihad) is referred to as a "jihadist." 


Scott Stewart is vice president of tactical analysis at and lead analyst for Stratfor Threat Lens, a product that helps corporate security professionals identify, measure, and mitigate risks that emerging threats pose around the globe.