A police forensic expert outside of a building where a 21-year-old Syrian refugee killed a woman with a machete and injured two other people in the city of Reutlingen, Germany, July 24, 2016.
Vincent Kessler / Reuters

A string of lone wolf terrorist attacks in France, Germany, the United States and elsewhere suggests that the phenomenon continues to spread and that it is growing increasingly lethal. Between October 2015 and August 2016 radicalized individuals, as well as “wolf packs,” carried out over 20 attacks in response to the Islamic State’s call to indiscriminately kill “nonbeliever” civilians.

The lone-wolf strategy benefits the Islamic State (also known as ISIS) in several ways. First, it is cheap and relatively easy. It requires no planning on its part or even contact with, or knowledge of, the perpetrators. Second, lone wolves frustrate preventive measures since they cannot be identified ahead of time, given they have no direct connection to ISIS, and in this way, shelters the group’s Western networks from possible exposure. Third, such attacks are damaging to both a nation’s psychology and its leadership, raising fear and inciting alarmism among civilians while making governments appear helpless and even incompetent. And fourth, the worldwide proliferation of lone-wolf terrorism boosts ISIS’ image, demonstrating its reach and appeal to both enemies and sympathizers.

A strategic logic also motivates the Islamic State to rely more on independent actors. With its defeats in Iraq, Syria, and Libya, the group is desperate for payback, and attacks by inspired supporters not only serve that purpose but are also an important force multiplier that works as a swarming tactic. A large number of uncoordinated attacks in a short period of time could upset the delicate balance of freedom and security in Western societies and bolster its own political objectives, such as using anti-Islamic sentiment in the West to feed its propaganda machine.

ISIS is hardly the first jihadi group to call for “leaderless jihad,” a term coined by Marc Sageman, an expert on terrorist networks. Al Qaeda preceded ISIS on this front, but with greater caution and much less success. After the United States crippled its operations following the 9/11 attacks, al Qaeda deviated from its original strategy and began promoting a decentralized jihad. Having lost its safe haven and training camps in Afghanistan, the group sought to reconstitute them in cyberspace and, through the Internet, disseminated training manuals and instructed followers on how to carry out attacks. The Saudi branch of al Qaeda even used the online journal, Mu’askar al-Battar, for virtual training. Several years later, its Yemeni branch produced Inspire magazine, which included instructional articles such as “How to make a bomb in the kitchen of your mom.”

French President Francois Hollande (R) and French Interior Minister Bernard Cazeneuve (L) arrive to take part in a minute of silence for the Nice attacks, July 18, 2016.
Bertrand Guay / Reuters

Notwithstanding these efforts, al Qaeda appeared restrained, at least compared with ISIS, in its use of lone wolves. Al Qaeda’s ambivalence stemmed from a fear of putting its trust in unknown and uncontrollable sympathizers. The indiscriminate violence of Abu Musab al-Zarqawi—the leader of al Qaeda’s Iraqi branch until his death in 2006 and the forefather of ISIS—harmed al Qaeda’s brand as a champion of the Muslim masses, and taught its leaders a hard lesson about the hazards of rogue agents. Burned by this experience, which cost the group support in Iraq and elsewhere in the Middle East, al Qaeda was thus wary of enduring yet another self-inflicted wound. In its view, an effective decentralized terrorist campaign requires, at the very least, articulating clear guidelines to ensure that the attacks align with the group’s strategic plan.

Even its leader, Osama bin Laden disapproved of an article in Inspire magazine that encouraged individuals to cover the front of a truck in razors and drive it into a crowd of civilians. He asked his lieutenants to convey to the Yemeni branch the dangers of such a method, which could potentially kill Muslims and undermine public support for the group. After bin Laden’s death, his successor Ayman al-Zawahiri continued to emphasize that indiscriminate killings, especially when they result in the death of innocent Muslims, could damage their cause. In 2013, he even introduced a document titled “General guidelines for jihad,” to help al Qaeda members and sympathizers understand the boundaries of “useful” violence.

The Islamic State, however, has little qualms about the use of indiscriminate violence. Whereas al Qaeda promotes selective targeting, in the service of a strategy that prioritizes dealing with the United States before the Middle East, ISIS embraces and encourages extreme brutality against an ever-growing number of “disbelievers.” It is comfortable with targeting Westerners, Shiites, and even other Sunni Muslims who refuse to accept its authority. It views all non-Muslims as legitimate targets and Muslim fatalities as acceptable collateral damage.

Naturally, when violence is the only goal, any attack by a lone wolf, regardless of psychological makeup or behavior, is a valuable contribution. ISIS only asks that its lone wolves leave a message—such as through Facebook or YouTube—before launching an attack, pledging allegiance to the group and its self-styled caliph Abu Bakr al-Baghdadi.

Although still relatively uncommon, lone wolf attacks are on the rise and their potential ramifications are considerable. Should it snowball, as more individuals find ISIS' goals attractive and legitimate, such attacks, in tandem with the Islamic State’s own directed operations, could exact hefty human and economic costs. But perhaps an even greater threat is their impact on Western societies as a whole.

When ISIS persuades Muslims, who are either Western citizens themselves or who simply live in the West, to attack close to home, it hopes to create a rift between non-Muslim and Muslim civilians in the West. The group is seeking to force Muslims in the West to pick a side—what ISIS has explained as erasing the “gray zone”—creating a clear division between “friends” (Muslims) and “enemies” (non-Muslims). Unfortunately, the xenophobic and Islamophobic declarations of some irresponsible populist leaders—as well as symbolic measures targeting Muslims such as the recent ban, by a number of French towns, of full-body swimwear or “burkinis"—is only aiding ISIS’ cause. Growing suspicion and even outright hostility toward Muslims do not mitigate the threat. They only strengthen it by breeding a sense of alienation and fueling radicalization. The result could be the erosion of the fabric of Western societies and the weakening of their fundamental principles.

The Israeli experience serves as a cautionary tale of the way in which fighting lone-wolf terrorism can deepen the divisions with societies. In response to a wave of terrorist attacks by young Palestinians, most operating on their own initiative, Israeli leaders called on Israelis to assist in neutralizing attackers. Civilians’ responsiveness has been a critical component in reducing the number and lethality of such attacks, but such outsourcing comes with a price. Empowered but often improperly trained Israelis fearful of any Palestinian-looking individual, ended up killing, instead of subduing, attackers, which further inflamed tensions. And in some cases of misidentification, innocent civilians were shot and lynched. Importantly, discrimination, and sometimes even outright violence, was directed at Israeli-Arabs, which has amplified the rancor within Israeli society. Western leaders would be wise to remember, especially when ISIS has made it so clear that it seeks to divide, that they must not create a society where arbitrary and often xenophobic criteria are used to separate “friends” from “enemies.”

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