Lone-Actor Terrorism: Can Anything Be Done?

The views and opinions expressed in this article are those of the author and do not necessarily reflect the official policy or position of the University of Birmingham

“Despite the perception that such violence is a 21st-century phenomenon, incidents of lone-actor terrorism date from at least the 19th century, with the first UK attack occurring in 1894.”


Violence, a period of sheer terror followed by gunshots and silence except for the moans of the injured. Twice now in a few weeks the United Kingdom has experienced attacks by individuals bent on murdering as many people as possible for ideological reasons.  In both cases, the attacks ended with the deaths of the perpetrators at the hands of the police. In the aftermath, there are the grieving families of the victims, the wounded and terrorised who were caught up in the assaults, and the questions of why do these acts of lone-actor terrorism keep happening and what can be done to prevent them in the future.

Lone-actor terrorism consists of ideologically motivated violence carried out by individuals who are not part of organized terrorist groups or following the direct orders of others (which is not to suggest that their ideological perspectives develop in a vacuum). They do so because of both macro and micro causes that intersect uniquely within individuals making broad efforts at deterrence difficult.   

Despite the perception that such violence is a 21st-century phenomenon, incidents of lone-actor terrorism date from at least the 19th century, with the first UK attack occurring in 1894. Nevertheless, the frequency of such attacks, including by the far right,  has grown over the last 10 years. According to a history of lone-actor terrorism I’m currently working on, since the terrorist attacks of 7 July 2005 in London, the vast majority of deaths (32 of 40) and injuries (301 of 349) from terrorism in the UK have been caused by lone-actor attacks.       

Perhaps somewhat counterintuitively, the increasing prevalence of lone-actor terrorism suggests that UK counter-terrorism tactics are working. We are never going to live in a society where terrorism is eliminated. Instead, it is about risk reduction, particularly of attacks with high casualties of the type that occurred in London in July 2005 and in Paris in November 2015. Generally, the prime threat of major attacks is posed by multiple attackers with skills related to the use of explosives and/or firearms. In the UK, these sorts of attacks are increasingly rare, in part because of the efforts of MI5 and various police counter-terrorism units around the country. Groups of attackers are easier to detect, intercept their communications, infiltrate through informants or undercover police officers, and ultimately, to stop.

Lone-actor terrorists are another matter entirely. Their attacks are often crude and rushed and involve everyday implements, such as knives and cars, that are readily available. That an individual convicted for terrorism offences, just released from prison, and under blanket surveillance by the police could still manage to carry out an attack as happened in Streatham illustrates the difficult task for those engaged in counter-terrorism. Despite vast increases in resources over the last 15 years, not all potentially dangerous individuals can be monitored continuously. Instead, a form of counter-terrorism triage occurs with the most serious threats given priority. The police have also worked on a speedy response with armed units once an attack is underway.

What more then can be done? First, some perspective is needed. Between  1 January 2019 and 31 January 2020, 157 homicides occurred in London, many of them through stabbings. Terrorism was responsible for two of that total. This is not to imply there isn’t a threat as, of course, the death toll from terrorism might be significantly higher if not for the resources put into countering it. But it does, suggest the need to avoid an overreaction.

The Johnson government will now rush to try to hold those convicted under terrorism offences longer in prison, a move that will undoubtedly be politically popular. The problem is, however, that these individuals will still eventually leave prison. And, of course, not all attackers have previously spent time in prison. Politicians won’t admit it for fear of a political backlash but the reality is that there will be more lone-actor terrorist attacks and little can be done to stop them.