Definition of ‘terrorism’

The definition of terrorism has been numerous and controversial at the same time. This essay will try and define the word ‘terrorism’ more clinically. Firstly, this essay will give background information of ‘terrorism’ and provide a definition which it believes is more clinical. Secondly, this essay will discuss the word ‘calculated’. Thirdly, the phrase ‘violence against non-belligerents’ will be discussed. Fourthly, the phrase ‘change the political, religious or other ideological landscape’ will be evaluated. Fifthly, the actors of the definition ‘individual, group or state’ will be assessed. Sixthly, the reasons for the exclusion of civilian, non-combatant, innocent, victim, illegal & illegitimate will be answered. Finally, a conclusion will be drawn. In each paragraph this essay will evaluate the strength and weakness and support it with relevant examples.

Terrorism background and definition

The definition of ‘terrorism’ has been an ongoing debate between academics, politicians and civilians. Terrorism is relative to the individual which means that the word ‘terrorism’ is determined by the person’s perspective (Jenkins, 1980, 10). To Palestinians, Israeli military forces shooting and killing stone throwing civilians is terrorism. On the other hand, to Israelis a Palestinian shooting rockets at Israel is terrorism. The complexity of this term means that scholars have not come up with a solidified meaning (Jones, Halibozek & Kovacich, 2008, 4 & Barker, 2003, 23) and this is backed by Laqueur (1977, 5) who argues that there is no definition of ‘terrorism’ nor will it be in the future. The subjectivity of defining terrorism, guarantees that it will be controversial.  As Tucker (1997, 51) encapsulates “above the gates of hell is the warning that all that enter should abandon hope. Less dire but to the same effect is the warning given to those who try to define terrorism”. Although the word ‘terrorism’ is multifarious this essay will seek a more clinical definition. Hence, the definition of terrorism as:

the use of calculated violence against non-belligerents to try and change the political, religious or other ideological landscapes, conducted by individual, group or state.


The definition consists of the word ‘calculated’ which means that there must be some intention and preparatory decision to execute an operation (Pillar, 2003, 13, Whittaker, 2007, 83 & Hoffman, 2006, 3). The reason why this essay included ‘calculated’ is because it wanted to avoid impulsive violence that may occur which this essay does not deem as terrorism such as the Portland Protests of 2016, which was a peaceful protest, who opposed Donald Trump, which then turned violent. Under this essay’s definition, this is not terrorism. Furthermore, this essay wanted to exclude opportunistic crimes such as the Unite the Right rally, in Charlottesville, in which one counter protestor died because of vehicle ramming. This was opportunistic criminality and not ‘calculated’ therefore it does not constitute as terrorism under this definition and this is backed by Pillar (2003, 13) who argues that evanescent tantrum or rage is not terrorism. Terrorist attacks need to have some components of calculation, for example the Charlie Hebdo attack or the 2015 Paris attack, showed elements of calculation.  This is backed up by Raymond (2003, 72) who argues that the foundation of terrorism is from a “premeditated, coldly calculated strategy of extortion”. However, the problem with ‘calculated’ is that we will never truly know if an act was calculated or not. Another problem is that most wars can also be included in this definition for example, the Iraq invasion of Kuwait was a calculated move and therefore is terrorism which puts the definition at a disadvantage because even though the definition is narrow, the word ‘calculated’ means this definition can be applied to most examples. 

Violence against non-belligerents

The use of ‘violence’, fear and force are very important to the definition and in defining terrorism (Prabha, 2000, 133 & Laqueur, 1999, 6). However, one of the weaknesses of this word is that ‘violence’ has various meanings and not all violence comprises as terrorism (Best and Nocella, 2004, 2 & Lindberg, 2010, 2). For example, bar brawls and gang fights (Laqueur, 1999, 6) are also violent, but are they considered as terrorism?. The problem with ‘violence’ is that it depends on your own perception of what composes violence. This is backed by Townshend (2011, 3) who argues that there is “no specifically terrorist action that is not already a crime under ordinary law”. However, the inclusion of ‘calculated’ rules out spontaneous bar fights or gang fights and even if they were ‘calculated’ this is still not terrorism under this definition because it needs to have a public motive which these are not. Nevertheless, another weakness of this is that ‘violence’ is a broad word in that it can mean several things such as emotional, verbal etc. This is backed up by Combs (2012, 6) who says that although ‘terrorism’ and ‘violence’ has become synonymous with killing lives, these words can instead mean that lives are negatively impacted or interfered instead of destroyed. For example, a few weeks after the 7/7 attack, a study was done in which 32% reported that they intend to travel less (Rubin, Brewin, Greenberg, Simpson & Wessely, 2005, 3) and this shows the emotional impact of terrorism. Nevertheless, the word ‘violence’ in this definition means physical and emotional against non-belligerents, thus its inclusion in the definition. This therefore excludes property which this essay deems not terrorism as solidified objects cannot project emotional or physical violence.

The addition of ‘non-belligerents’ is very important because this definition wanted to exclude politicians and military personnel who are not ‘non-belligerent’ and it wanted to narrow the definition of victims. Politicians authorise wars and thus are not exempt from the word civilian or non-combatant. In addition, this essay believes that ‘terrorism’ should still carry negative connotations because killing against non-belligerents is morally wrong, thus its inclusion. For example, under this definition, the 2009 Fort Hood shooting is not terrorism because they are not non-belligerents they are military personnel and the murder of Jo Cox is not terrorism because she was a politician. In addition, the 2001 Indian Parliament attack, under this definition, is not deemed as a terrorist attack because it targeted politicians. However, the Manchester Arena bombing, under this definition, is a terrorist attack because it was a calculated attack on non-belligerents. In addition, anarchist acts are also not deemed as terrorism because they mostly target government and politicians. For example, president McKinley’s assassination by Czolgosz, who was an anarchist, is not deemed as terrorism because McKinley is a belligerent. Under this definition, ‘terrorism’ targets non-belligerents, this will exclude groups engaged in guerrilla, separatism, independence and civil warfare because they usually target belligerents. But, this essay acknowledges that some, within these groups, can commit terrorist acts under this definition. However, this is a weakness because ‘non-belligerent’ has many meanings. For example, the US State Department (2004, 12) interprets non-belligerent as “civilians, military personnel who at the time of the incident are unarmed and/or not on duty… attacks on military installations or on armed military personnel when a state of military hostilities does not exist at the site”. Under this definition, the murder of Lee Rigby is terrorism however, under the essay’s definition that is not terrorism because Lee Rigby was a soldier and therefore a belligerent. In addition, some argue that ‘non-belligerent’ does not need to be included to identify terrorism (Philipps, 2015, 227) and this is seen in Hoffman’s definition where there was no mention of a target. This essay acknowledges that there is a grey area in the middle of ‘non-belligerent’ which is another weakness. For example, there are politicians who have opposed wars, such as Ken Clarke, but under this definition their death would not be terrorism. In addition, the plane that attacked the pentagon during 9/11 is not terrorism; however, there were non-belligerents on the plane which poses a problem if this incident should be considered ‘terrorism’ under this definition.

Change the political, religious or other ideological landscape

The most important feature of the terrorism is its aim to change the ‘political, religious and ideological landscape, or create a fearful state of mind’. The reason why this essay included this is because it wants to further distinguish acts of criminality and acts of terror. The difference between the two is that acts of terror are motivated by political, religious or other ideological change (Hoffman, 2006, 2) whereas acts of criminality are not. Also, he distinction between the two is the purpose of the violence. This is backed by Tofangsaz (2015, 381) who argues that criminals have a personal motive, whilst terrorist have “a public motive”. Therefore, there must be public motivation for an act of violence to be considered ‘terrorism’ under this essay’s definition. The exclusion of a public motive in an act of violence is viewed as an idiosyncratic or personal motive and subsequently, can only exclusively be seen through the prism of ordinary criminality. For example, the 2017 Las Vegas shooting, under this definition, is not terrorism because there was no public motive. However, the Norway attack, committed by Anders Breivik, is terrorism because it had a public motive which was the trepidation of the spread of Islam (Richards, 2014, 43). The two examples are used to emphasise the importance of including ‘political, religious or other ideological landscape’ in the definition of terrorism, as without this inclusion, then many privately motivated violence can be classified as terrorism, such as mafia activities or the Sandy Hook shooting, which this essay wanted to avoid.

Conducted by individual, group or state

The final part of the definition is the actors involved in terrorism such as ‘individual, group or state’. All three actors can commit calculated, public terrorist acts against non-belligerents to try and change the political, religious or other ideological landscape which is why it was included in the definition. The inclusion of ‘individual’ was due to the rapidly changing nature of terrorist acts. In recent years terrorist acts have increasingly been conducted by so called ‘lone wolf’ attacks or by small groups who have no affinity or connection to a recognised and established syndicate (Michael, 2012, 1). For example, the Bastille Day attack or the Orlando shootings were both lone wolf attacks. In addition, the ‘group’ in the definition, regards to a group of people who have a shared identity and use calculated, publicly motivated, violence against non-belligerents to try and change the political, religious or other ideological landscapes. The last, more controversial and significant part is the addition of ‘state’. The inclusion of ‘state’ was because states can also commit terrorist acts (Cordesman, 2001, 12) which are morally problematic and so this essay did not want states from escaping the definition. For example, the classic case of the US invasion of Iraq, under the essay’s definition, is ‘terrorism’ because it was calculated violence, using shock and awe tactics, against non-belligerents to try and change the country’s political or other ideological landscape. Moreover, the Korean Air Flight 858 exploded because of North Korean agents, which killed everybody on board which is also state terrorism as it fits the criteria of the definition. However, others argue that ‘states’ should not be included (Laqueur, 1986, 89) because there is a difference between state and non-state violence. State violence is regulated by rules and customs whereas non-state violence has broken all the rules and customs (Hoffman, 1998, 34). However, the problem with this is that there is nothing to prove that states follow the rules and the truth is that states do violate rules and customs (Blakeley, 2012, 2) as seen with US torture in Iraq and Afghanistan.

Exclusion of civilian/non-combatant, innocent/victim & illegitimate/illegal

The reason why ‘civilian’ and ‘non-combatants’ was excluded was because it excludes politicians which this essay deems not civilians or non-combatants. More importantly, words like ‘innocent’ and ‘victim’ were excluded because these words depend on the individual’s perception of who is innocent and a victim. Furthermore, the words illegitimate & illegal were excluded because it depends on the moral compass of the individual to determine whether an act was illegal or not. Importantly, ‘non-belligerent’ is the main illegitimacy of the act thus the exclusion of illegitimate & illegal.  


The aim of this essay was to give a definition of ‘terrorism’ but the subjectivity of this word, guarantees that it will be contentious. The difficulty of defining ‘terrorism’ is that the reasons, motivations, goals and tactics are different in each case and it is further made problematic by the associations linked with terrorism. The contentious nature of ‘terrorism’ means this will always be debated by scholars, politicians and others in the considerable future, the aim of the essay was to provide a definition that is clinical, but by doing this it has opened itself up to criticism. The definition has been carefully crafted and has provided a satisfactory defence for the words and phrases needed to categorise an event as terrorism. As Wittgenstein (1961, 6.522) says, “there are, indeed, things that cannot be put into words”, the word ‘terrorism’ is one of them.


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