Chart of the week: Trends in political violence in the United States

A recent rise in far-right terrorist attacks  in the United States could form part of a recurring trend of violence stemming back to the 1700s.

Data on political violence in the United States (US) suggests that the increase in far-right terrorism and other forms of extremism are part of a broader cycle of increased political violence that has occurred approximately every fifty years for the past two centuries.  All of these periods were marked by significant socioeconomic and cultural unrest, particularly over the issues of group grievances and labour relations.

Over the last four years, far-right terrorism in the West has increased by 320 per cent. Last year in the US, 28 out of 57 terrorist events were committed by far-right extremists.

According to the Institute for Economics and Peace (IEP), there are two reasons why this cycle appears to reoccur every 50 years. Firstly, there are specific deteriorations in certain aspects of Positive Peace, which make the political climate particularly susceptible to an outbreak of violence. Secondly, there are the dynamic aspects of violent conflict, in which violent activity becomes contagious and increases rapidly, until resources devoted to combatting it increase, and the popular moods turn against conflict and towards reconciliation.

Positive Peace is the attitudes, institutions, and structures that help build and maintain peaceful societies. A fall in Positive Peace greatly increases the risk of instability and violence. IEP’s Positive Peace Index identifies factors that are most strongly correlated with an absence of violence, and is measured by 24 indicators across eight domains.

At times of extreme political and cultural polarisation, as levels of Positive Peace deteriorate, the likelihood of an increase in violence increases, and individuals and groups who are ideologically disposed to violence become much more likely to carry out attacks. The impact of this violence on individuals who are more likely to be radicalised depends on the distance in time from previous cycles of violence. The cultural memory of the impact of previous waves of violence is lost, thus leading to period where violence is more attractive, and exposure to violence is more likely to radicalise individuals.

Over the past decade, there has been a noticeable reduction across many Positive Peace indicators in the West, particular in the US. The Positive Peace Index score for the US declined by 6.7 per cent from 2009 to 2018. Only Libya, Greece, and Syria had larger declines over that time period. The most noticeable deteriorations occurred on the Low Levels of Corruption, Free Flow of Information, Acceptance of the Rights of Others, and Equitable Distribution of Resources Pillars.

The data is taken from the US Political Violence Dataset, which counts violent events (lynchings, terrorism, rampage shootings, assassinations, and riots) that result in at least one fatality. Whilst data from this source is only available up until 2010, IEP calculations suggest that there has been a significant increase in violent political events from 2010 to 2019.