Matthew Levitt is the Fromer-Wexler Fellow and director of the Stein Program on Counterterrorism and Intelligence at The Washington Institute.

By Matthew Levitt –  Foreign Policy – September 21, 2016 – America’s latest terrorist incident shows why the preferred metaphor to describe such attacks is usually a contradiction in terms.

22 Sep 2ß16 – It was no surprise that in the first hours after the New York and New Jersey bombing attacks, the culprit was widely suggested to be a “lone wolf.” The term, used to describe an individual inspired by others but acting on his or her own, has become the counterterrorism metaphor-of-choice in the age of the Islamic State. It’s time, however, to put the lone-wolf metaphor, and its associated counterterrorism analysis, out to pasture.

According to Secretary of Homeland Security Jeh Johnson, we now live in a world where terrorism is “carried out by those who live among us in the homeland and self-radicalize, inspired by terrorist propaganda on the internet.”

But if that diagnosis isn’t wrong, it is incomplete. The New York bomber may have been “self-radicalized,” but it’s very unlikely he was merely “inspired” by terrorist groups.

There’s no doubt the Islamic State has been exceedingly explicit, and calculating, in its calls for lone-wolf attacks. In an online e-book titled How to Survive in the West: A Mujahid Guide (2015) the group argued: “With less attacks in the West being group (networked) attacks and an increasing amount of lone-wolf attacks, it will be more difficult for intelligence agencies to stop an increasing amount of violence and chaos from spreading in the West.” The group’s call to action has been amplified, first, by its talent at promoting it through social media (the Mujahid guide was distributed widely on Twitter), and second, the authority lent to the group by virtue of its participation in the Syrian war and its purported re-establishment of the caliphate.

Clearly, this has had some effect. In recent years, the pool of potential homegrown terrorists has expanded: Today there are open investigations on about 1,000 potential homegrown violent extremists in all 50 states. And yet, not all of America’s radicalized individuals have been motivated by the Islamic State’s appeals for lone wolves. Ahmad Khan Rahani, the suspect believed to have been behind the bombings in New York and New Jersey, reportedly was inspired by the U.S.-born al Qaeda cleric Anwar al-Awlaki — who was killed in 2011 by a U.S. drone strike in Yemen, but whose radical preaching lives on in online videos. He traveled to Pakistan and Afghanistan, areas where al Qaeda and the Taliban are more prevalent than the Islamic State. A note apparently left by the bomber referred to Awlaki and the Boston Marathon bombers, who were also inspired by Awlaki.

The more fundamental problem with references to “lone wolves,” however, is that the term is largely a misnomer. Since wolves are pack animals, “lone wolf” is meant to conjure the image of someone who has rejected his nature and is now acting completely independently — a rogue individual operating outside the scope of any cell, network, or group. But while there are cases of inspired individuals — often people from broken homes, with criminal records or histories of mental instability — who attack on their own with no formal ties to any group, those rare cases are the exceptions that prove the rule. More often than not, evidence indicates that suspects thought to have been lone wolves might more accurately be described as known wolves — people whose radicalization, suspicious travel, and changes in behavior were observed by acquaintances.

That already appears to be the case with Rahani. He apparently traveled to Pakistan in 2005 and then again for three months in 2011. More recently, he lived in Quetta — home of the Afghan Taliban Shura Council — for nearly a year until March 2014; a younger brother said he had also visited Afghanistan during that time. On his return to New Jersey, locals now report having noticed — but not reported to authorities — a distinct change in Rahani’s behavior. It was around this time that Rahani’s father told the police that his son was a terrorist, following a domestic incident in which Rahani was accused of stabbing his brother. But the father soon recanted, and the FBI never opened an inquiry.

It’s not just the pattern of his travels that suggests Rahani’s radicalization wasn’t primarily mediated by the internet. Based on the sophistication of the bombs Rahani purportedly constructed, authorities suspect he received some sort of personalized explosives training. “If you’re working off the premise that the guy made all these devices,” a law enforcement official commented, “then the guy is a pretty good bomb-maker. And you don’t get that good on the internet.” In other words, the evidence points to the New York and New Jersey plots being something other than the work of a lone wolf.

That’s not to suggest Rahani was anything like a terrorist mastermind. The poor target selection of the New York bombings — wastebaskets and dumpsters in unremarkable locations — raises plenty of questions about the extent of his training, and the amount of support he may have received from more experienced terrorists in carrying out this attack.

Some will be quick to criticize the FBI for not taking further action after briefly investigating Rahani two years ago. But the truth is that the challenge for law enforcement is immense. Increasingly, U.S. counterterrorism officials view the terrorist threat as a spectrum, from inspired individuals acting alone to terrorist operatives acting at the direct orders of Islamic State leaders in Syria. But rarely are cases clearly at one end of the spectrum or another. “More often than not,” National Counterterrorism Center Director Nicholas Rasmussen explains, “we observe a fluid picture where individuals operate somewhere between the two extremes.”

“We are looking for needles in a nationwide haystack,” FBI Director James Comey testified in July, “but even more challenging, we are also called upon to figure out which pieces of hay might someday become needles. That is hard work, and it is the particular challenge of identifying homegrown violent extremists.” Determining whether Rahani was already radicalized two years ago or if that only happened later is sure to be a central part of the FBI’s post-bombing investigation.

As the investigation unfolds it will quickly become clear whether Rahani was radicalized over a long period or, as is now frequently the case, converted to radicalization in a quick and concentrated process. “We knew of several Paris-related suspects before,” a Belgian police officer told me just days before the Brussels bombings in March, “but not for terrorism reasons, just petty crime and small incidents.”

We will also learn whether he qualifies as a homegrown violent extremist whose radicalization process started in the United States, or if he was exposed to radicalism only on his trips abroad. Most critically, authorities will determine whether he carried out the attacks on his own, or if he received assistance from others here in the United States or abroad.

Rahani may turn out to be a lone offender, but he is unlikely to be a truly lone wolf. In all likelihood, he too will fall somewhere in the middle of the fluid terrorist spectrum. And given the evidence available so far, he may have more to do with al Qaeda — the persistent terrorist group many have already forgotten — than the still dangerous but now decaying Islamic State.