America’s lone-wolf terrorists are unpredictable in almost every regard—except one

A single person can devastate the lives of thousands.
A single person can devastate the lives of thousands.
Image: Reuters/Carlo Allegri
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Over the past two decades, lone-wolf attacks have become the dominant form of terrorism in the US, and now top intelligence and law enforcement officials’ list of concerns. Jeh Johnson, the US secretary of Homeland Security, says he has placed homegrown violent extremism at the “front and center” of counter-terrorism efforts. “The thing that most keeps me up at night is the next Orlando [or] San Bernardino-type attack by someone who has radicalized in secret,” he said at the Aspen Security Forum in July.

Lone-wolf terrorist attacks are extremely difficult to prevent because assailants operate solo and, therefore, often under the radar of law enforcement. Their motives are frequently a tangle of personal and political grievances, societal alienation, and mental health issues.

While much remains perplexing about sole perpetrators, data shows one thing for sure: they almost always use guns.

This wasn’t always the case. In one of the most famous examples of American homegrown terrorism, Eric Rudolph carried out a string of attacks in the southern US from 1996 to 1998, killing two people and injuring more than 100 with homemade bombs. His use of homemade devices was hardly out of the ordinary.

In a forthcoming book, The Age of Lone Wolf Terrorism: A New History, Mark Hamm, a criminology professor at Indiana State University, and Ramón Spaaij, a sociologist at Victoria University in Australia, compiled a comprehensive database of lone-wolf terrorist incidents in the US from 1940 to mid-2016. They found that in the six decades preceding the 9/11 attacks, there were 144 lone-wolf terrorism incidents, 47% of which involved explosives, and 42% of which involved firearms. Post 9/11, lone-wolf terrorism has become exceedingly common—there have been 105 attempted attacks in less than 15 years—and just 11% involved explosives compared to 74% involving guns.

Moreover, in the post-9/11 world, essentially none of those attempted bombings did much of anything. Prior to 9/11, there were 234 lone wolf terrorist bombing victims, compared to a mere six victims of such bombings in the past 15 years, all the result of anti-government extremist Luke Helder’s foiled plot to plant pipe bombs across the US.

One explanation for the shift is the proliferation of laws making it harder for individuals to build bombs. In the years following the 1993 World Trade Center bombing and the 1995 Oklahoma City bombing, Congress amended the Organized Crime Control Act of 1970 to enact tighter controls for the marking, sale, and transfer of explosive materials. Through other laws, such as the Antiterrorism and Death Penalty Act of 1996 and the Safe Explosives Act of 2002, Congress strengthened the licensing and permitting requirements of manufacturers, dealers, and users.

Not so with guns, where legislation has actually somewhat relaxed. In 2004, Congress did not renew its 10-year federal ban on the manufacture and possession of semiautomatic assault weapons and large-capacity magazines. Laws that protect manufacturers and dealers have also been passed. The 2003 Tiahrt Amendment, for example, prohibits law enforcement from publicly releasing data showing where criminals buy their firearms, and requires the FBI to destroy all approved gun-purchaser records within 24 hours. The Protection of Lawful Commerce in Arms Act, passed two years later, gave manufacturers and dealers broad immunity from civil lawsuits.

There has also been a surge in the number of guns manufactured in the past decade, according to the Bureau of Alcohol, Tobacco, Firearms and Explosives. About 3 million firearms were manufactured in 1986; by 2014, that rose to over 9 million.

ATF data also shows that while firearm exports increased from around 200,000 in 1986 to 400,000 in 2014, imports increased from 700,000 in 1986 to 3,900,000 in 2014, which means there are many more guns coming in than going out.There are now approximately 350 million guns in the US—the most ever—equal to about 116 guns per 100 Americans.

In his eight years as president, Barack Obama has addressed Americans 18 times in the wake of mass shootings, all of them perpetrated by sole assailants. After a shooting in Orlando, Florida, that resulted in 49 fatalities, Obama told the nation: “We make it very easy for individuals who are troubled or… want to engage in violent acts to get very powerful weapons, very quickly.”

While a whole national-security apparatus has been built around combating terrorism, it is undermined by laws that allow would-be terrorists, including those already under suspicion and on the terrorist watchlist, to legally buy firearms. As Adam Gadahn, a former al-Qaeda spokesman who was killed in a drone strike in 2015, put it in a 2011 video:

America is absolutely awash with easily obtainable firearms. You can go down to a gun show at the local convention center and come away with a fully automatic assault rifle without a background check and most likely without having to show an identification card. So what are you waiting for?

By some estimates, mass shootings are also occurring more often—and becoming more lethal. “Easy access to guns coupled with extensive media attention makes a mass shooting a more attractive option for a terrorist,” says Adam Winkler, author of Gunfight: The Battle Over the Right to Bear Arms. As individuals see successful firearm attacks, they start copying those tactics—making these attacks more frequent, and subsequently more frequently copied, says Michael Jensen, a researcher for the Global Terrorism Database, at the National Consortium for the Study of Terrorism and Responses (START). It’s a deadly cycle.

One of the most commonly wielded weapons in mass shootings and lone-wolf terrorist attacks is the semi-automatic Glock pistol. The handgun is a fast, easy, and accurate way to put rounds in a target, and Hamm says it “has achieved celebrity status amongst lone wolves.” It’s a strong argument for making handguns a part of any gun reform measures.

Ultimately though, it’s just a lot easier and safer to use a firearm than it is to successfully build a bomb. Bomb making requires a certain level of expertise, and there’s always a chance it may explode in your hands, or not explode at all. (Look no further than the recent undetonated bomb in Manhattan, left by Ahmad Rahami, or most of the other undetonated devices in post-9/11 bomb plots). “Bombs are unpredictable—you’re leaving a lot to chance,” says Jensen. “Guns are very accurate.”

That reliability becomes more crucial as terrorists shift from targeting buildings to targeting people. In the past, Jensen says, terrorists typically went after what researchers call “hard” targets, protected structures such as military installations or government facilities. Now, they are much more likely to attack “soft” targets—unprotected places full of civilians, such as malls or restaurants.

“While attacks involving arson or explosives may be intended to cause only property damage, or both property damage and human casualties, firearms are more often used in attacks aimed at causing human casualties,” reads research compiled by START. The group’s data show that terrorist attacks with firearms are much more lethal.

This is further supported by Hamm’s findings, which suggest that the lethality of lone-wolf terrorism has been at an all-time high since 2011. The average number of people killed or injured per sole assailant spiked to 8.3 in the 2011 to mid-2016 period, from 2.45 in the previous decade. There have been 235 killed or injured since that spike, almost all of them from firearms, whereas the previous decade saw a total of 105 victims of lone-wolf terrorist attacks.

Brian Jenkins, a renowned terrorism researcher at RAND, was once fond of saying that terrorists want a lot of people watching, not a lot of people dead. “At the time that he made the statement, terrorism in many parts of the world was mostly demonstrative, meaning that it was about drawing attention to a cause and not necessarily about killing or injuring people,” Jensen says. Jenkins updated his statement in 2006; today’s terrorists “want a lot of people watching and a lot of people dead.”

“Today, most terrorist organizations try to be as destructive as possible,” echoes Jensen. As groups like the Islamic State gain notoriety for their lethality—and expressly promote the killing of civilians to their followers—other groups emulate them. ISIL glorifies those groups for their imitative actions, further encouraging potential lone wolves. And so the vicious cycle continues.