In 2018, a 50-year-old man was arrested in Florida. He had sent explosive devices to George Soros, Hillary Clinton, Barack Obama, CNN’s New York offices, Robert De Niro, Joe Biden, and Senator Cory Booker, and a few others. It was a seemingly unconnected set of targets, at least at first glance. But they did have one thing in common: they had all criticized (and been criticized) by then-president Donald Trump.

The terrorist plot was ultimately foiled and the perpetrator was convicted. It was a pro-Trump terrorist act, with the perpetrator driven in part by his obsession with President Donald Trump and his feeling that Democrats were to blame for damage to his van, which had been plastered with Trump stickers and images of crosshairs superimposed over the faces of Trump opponents.

It’s a crazy, lone-wolf terrorism act, many said at the time; and in a sense, they were right. But researchers who were looking at things more closely saw a concerning trend: the rise of stochastic terrorism.

Stochastic, in a general sense, means something that is described by a random probability distribution. Stochasticity is akin to randomness and the two terms are often used interchangeably, although technically speaking, the former refers to a modeling approach while the latter refers to phenomena themselves. So how exactly can terrorism be stochastic, or random?

Stochastic terrorism is defined as isolated acts of violence or terrorism committed by random, typically “lone wolf” extremists, but triggered by political demagoguery. They are acts that are statistically predictable but individually unpredictable — we know that they are likely to happen, but it’s hard to say when or where. The acts are individually random, but the trend is predictable.

It’s a fairly new concept, but one that may warrant closer attention given the polarization in the US and several other countries.

The term was coined in 2002 by Gordon Woo, a catastrophe expert who spent years designing computer models for numerous catastrophes, including terrorism. Woo wrote that there may be a quantifiable relationship between seemingly random acts of terror, especially amplified through the lens of mass media. Woo theorized that “the absolute number of attacks within a year, i.e. the rhythm of terror, might ultimately be determined as much by publicity goals and the political anniversary calendar as by the size of the terrorist ranks”. This fits perfectly with the 2018 case.

Being hostile to political opponents is not a new idea, but President Trump’s vitriol took it to an unprecedented level, at least for what was seen in the US. At rallies and in front of supporters, he would insult opponents and incite violence, using scorching rhetoric that many saw as dangerous. From a stochastic terrorism perspective, things make a lot of sense.

Under the guise of plausible deniability, President Trump isn’t liable for any individual attack. But in the grand scheme of things, his behavior may have caused an increase in acts of terrorism. It fits: individually, all the attacks were unpredictable but taken together, it was bound to happen. We may be seeing stochastic terrorism in action.

Stochastic terrorism on the rise

It’s more than just dog-whistling — it’s an emboldening of violent acts that was felt throughout Trump’s presidency. Numerous violent actors either invoked Trump or his rhetoric, and this is unlikely to be a coincidence. The mass shooter who murdered 22 people in El Paso, Texas, in 2019, spoke of a “migrant invasion” in the United States. Just 24 hours later, a man in body armor bearing a rifle went on a rampage in Dayton, Ohio, killing at least 9 and injuring dozens. He had described this act as “a response to the Hispanic invasion,” accusing Democrats of “pandering to the Hispanic voting bloc,” and condemning “race mixing” and “interracial unions,” as well as “fake news”.

This all escalated after the elections when, called to action by Trump, thousands of supporters gathered in Washington DC. Many from this crowd ended up storming the Capitol building, assaulting Capitol Police officers and reporters, erecting gallows on the Capitol grounds, and attempting to locate lawmakers to capture and harm. The rioters vandalized and looted the offices of several members of Congress. The FBI later characterized the incident as domestic terrorism.

“We love you. You’re very special,” Trump told the mob, looking directly into the camera. “I know how you feel.”

Of course, stochastic terrorism isn’t a Trump-specific term. While the former US president did take things to a level America hasn’t seen before, this type of inflammatory rhetoric meant to incite to radicalize others and incite them to carry out acts of terror has been used before. ISIS and Al-Qaeda are two of the most infamous groups to use this approach as a method of gaining supporters. Anti-abortion religious extremists also do it.

In their 2017 book Age of Lone Wolf Terrorism, criminologist Mark S. Hamm and sociologist Ramón Spaaij explain stochastic terrorism as a form of “indirect enabling” of terrorists. They name Anwar al-Awlaki as a good example. A former prominent Al-Qaeda member killed by a US attack in 2011, al-Awlaki denied being a member of the terrorist group, yet intelligence efforts show he was gathering new recruits for the terror group through his online lectures. Al-Awlaki influenced several other extremists to join terrorist organizations overseas and carry out terrorist attacks in their home countries. Few would argue against the idea that that he engaged in stochastic terrorism.

However, the book also names show host Alex Jones as a stochastic terrorist. Jones’ website and show (InfoWars) is derived from conspiracy theories and often features insults and hate speech. Jones has promoted numerous conspiracy theories, some “tamer” (like climate change being fake or that there is a “New World Order” controlling the world), and some pretty crazy. Among others, he claimed that HIV is a government-made virus, that the 2012 Sandy Hook Elementary School mass shooting was “a hoax”, that there is an ongoing genocide against white people, and that the government is using chemicals to turn people (and frogs) gay — yes, really.

In the 2010 Oakland freeway shootout, the shooter cited conspiracy theories peddled by Jones as an influence for his crimes. Jones was ordered to pay $100,000 for his claims that the 2012 Sandy Hook massacre of school children was a hoax. But he continued to air his ideas.

A stochastic process

The problem with stochastic terrorism is that it’s so easy for any instigator to invoke plausible deniability. No one told an individual shooter to go out and kill people, and there’s no real liability chain. But according to a growing chorus of expert voices, stochastic terrorism is on the rise, especially in the US. Ironically, as terrorism is falling around the world, it’s increasing inside the US, fueled by right-wing and religiously-affiliated groups, as Quartz’s Luiz Romero writes. Around the world, attacks fell from about 17,000 in 2014 to about 11,000 in 2017, and dropped almost 40% in the Middle East. In the US, there were only six attacks a decade ago, but there were 65 of them in 2017. The motivation of terrorists is changing too. Increasingly, US terrorists display racist, anti-Muslim, homophobic, anti-Semitic, fascist, anti-government, or xenophobic motivations.

Out of 65 incidents, 37 were tied to the above-mentioned right-wing views, compared to 7 linked to Islamic extremists and 4 linked to left-wing ideology. The rhetoric of Donald Trump was arguably a factor in this. The impact is amplified by actors such as Alex Jones; and lastly, mass media and social media also play a role.

In 2011, after the shooting of US representative Gabby Giffords, a Daily Kos blog warned of the rising threat of stochastic terrorism. It made an important point: media agitators incite attacks by random “nuts” — and even as the “nuts” get caught, the stochastic terrorist is given more prime time. The stochastic terrorist may not even realize what he or she is doing (like a drunk driver) or may be deliberately doing it, but it matters less.

“The stochastic terrorist then has plausible deniability: “Oh, it was just a lone nut, nobody could have predicted he would do that, and I’m not responsible for what people in my audience do.” The lone wolf who was the “missile” gets captured and sentenced to life in prison, while the stochastic terrorist keeps his prime time slot and goes on to incite more lone wolves,” the post read.

The problem is that with social media, the ‘lone wolf’ phenomenon is amplified even more. No matter how extreme your views are, you can find groups where your ideas are shared.

That these media agitators get continued prime-time attention has been showcased over the past few years. In his election campaign, then-candidate Trump ‘joked‘ that “Second Amendment people” (gun owners) might “do something” if Hillary Clinton won the election. The ‘Lock her up’ chants at Trump rallies became a bizarre running gag.

But something is starting to change, and some progress is being reported — not from a counterterrorism or policy perspective, but from a big tech perspective. Notably, Alex Jones was de-platformed from virtually all major social media websites. He was banned from Youtube, Spotify, Facebook, Twitter, Instagram, Pinterest, everywhere he tried to go, he was banned. The official reason that these platforms offered was hate speech. Apparently, misinformation (or disinformation, the deliberate spread of wrong information) is fine, but hate speech is not. Alex Jones’ Infowars had fallen into that last category and therefore was banned. However, it’s not clear exactly why action was not taken earlier, since hate speech had arguably been common at Infowars for years.

Social media platforms danced around Trump’s hate speech and misinformation as well. Twitter started flagging some of then-president Trump’s claims as inaccurate or misleading. Facebook trod cautiously, but after the Capitol was stormed by Trump supporters, it banned Trump, and so did Twitter.

“Progress in this space is tough but we’ve never been as committed and as focused in our efforts,” a recent Twitter press release read. “Serving public conversation and trying to make it healthier is our singular mission here.”

But if our strongest line of defense against stochastic terrorism is big tech, we’re probably in for a wild ride. Hate speech thrives on social media, and action is too little, too slow, and not transparent. Social media is a place where hate speech thrives, often in unconventional ways. A recent study found that racist and neo-fascist ideals are often presented as humorous jokes and memes, to make them more accessible and help them spread more. 

Trump, Alex Jones, and Al-Qaeda all showed stochastic terrorism can work in different ways and we don’t have any clear roadmaps to combat it. But whatever this roadmap may be, it likely won’t be a silver bullet and will likely need multiple things to come together. It remains to be seen whether the recent trends will continue during Biden’s presidency.