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Terrorism Essay In Simple Language Definition

What is terrorism?

This essay was written in 2006. I no longer agree that a clear and useful definition of terrorism is possible. In another essay (written slightly later in 2006, but which I don't have a copy of) I argued this very point, against the possibility for there to be a meaningful definition of "terrorism". Terrorism is a term used to vilify and create hatred against certain groups or about certain acts, it can not be a "morally neutral" term. And a note from 2014, I'm not the only one to think that, see also Terrorism: the most meaningless and manipulated word (2010) and On the UK’s Equating of Journalism With Terrorism (2014) both by Glenn Greenwald.


What is terrorism? Terrorism is a term that is used to describe acts depending on the politics of the person and of the time. Not only are there genuine disagreements in definitions,1 but also the political atmosphere affects the meaning of the word. Terrorism is an "ideological construct", an essentially contested term.2 This essay will attempt to determine if it is possible to arrive at a 'working definition' of terrorism. It will do this by first outlining some characteristics of a 'working definition' and will look at problems associated with creating a working definition for terrorism. Problems with associated with how the words 'terrorism' and 'terrorist' are used are also outlined. A possible definition is then given with an explanation and clarification. A brief examination of different forms of political violence will follow.

What is working definition?

It is impossible to find a definition of terrorism that everyone will agree on, but this is not important in itself, except for linguists.3 However, this is not what a working definition is. A working definition is a definition that can be used in a particular area by a particular group. So a working definition in the UN might be different to a working definition in an academic discussion (however, there exists no UN definition4 because of differences in politics and perception between nations5). A working definition of terrorism has a number of characteristics.

To be workable, a definition of terrorism has to be black and white. It cannot have any shades or possibles. Using the definition a person should be able to look at an act and (if they know sufficient facts about that act), be able to classify it as terrorism or another type of act (criminal for example). Use of the words 'generally'6 or 'usually'7 do not make a definition useful as it leaves open other acts not in the definition.

A terrorism definition has to be morally neutral. Different moral sets may allow different acts, for this reason any definition has to exclude the possibility of moral bias.

A definition needs to be useful and meaningful, it can not be too broad and cannot shift definitional problems to another word (such as 'legitimate' or 'non-combatant'), unless these words are also defined in the definition. A broad definition of terrorism is useless for moral,8 criminal and academic purposes.

A working definition can also not be too large. A long definition becomes unwieldy and unusable. A definition proposed in 1988 has one hundred and seventeen (117) words9, and while it was supposed to be an 'academic consensus' the length means that it is not useful or usable.

A definition has to focus on the act, rather then the actor.* No group, state or 'liberation' movement should be excluded.10 The reason for this is that it makes it clear that certain types of act are the same, no matter who commits them. While there maybe differences between criminals, who are motivated by personal gain, and 'terrorists', who are motivated by some 'higher good', and psychopaths, who kill for pleasure, or others with 'mental disorders', in why they commit acts, they maybe similar acts. The only difference maybe the spoutings from their mouths or perhaps the actual result of the act within the group. Ignoring the actor is also another part of not having a moral bias; an act cannot be excused from being terrorism because one group committed it rather then another.

These characteristics provide a framework for creating a definition that is usable in many different scenarios and will the basis for creating a 'working definition', and could be useful in investigating other definitions.

Problems associated with creating a working definition

As mentioned in the introduction there are a number of disagreements in definitions of terrorism. These include property damage, the infliction of terror, and the reason why the act is committed and so on. The Australian Criminal Code includes "serious interference with essential electronic systems" in its definition.11 This raises the question of what else could be considered terrorist acts in this case, about can attacks on other essential infrastructure, 'cyber' attacks or blocking radio frequencies (such as those used by mobile phones and emergency services)? Can attacks on the economy (by for example attacking the stock exchange) in a non-violent manner be considered terrorism? The Economic Analytical Unit (part of the Australian Government's DFAT) include attacks on natural gas pipelines (which are disruptive to business) as "terrorists attacks".12 Does terrorism have to 'terrorize' as Anthony M. Burton argues?13 Or can it simply destroy? Does it have to have an aim to 'coerce'? Or can it be an act without any obvious demands?14

There are always two points of view (at least) when considering a terrorist act. There is that of the terrorist themselves, and that of other people. When talking about motive and intent, as well as the non-combatant, civilian status or innocence of a target, a definition has to consider these from the point of view of the terrorist. This helps to remove problems of subjectivity. Though this might be problematic in some cases if the actor does not believe that there are any innocents (such as the Frenchman Emile Henry who in 1894 said (at least among the ruling class)).15

Problems of usage

The words 'terrorism' and 'terrorist' are pejorative and have a lot of negative emotional and political connotations.16 They have also been misused quite often, for these reasons it is preferable that the word is not used unless strictly necessarily. The use of the words closes debate and inquiry. 17

The word terrorism has spawned others such as 'eco-terrorism', that do not fit within the traditional meaning of terrorism. The word 'eco-terrorist' is a against both by those who damage the environment (e.g. clear felling forests) and those who commit acts of property damage to protest damage to the environment.

People talk about terrorist groups or insurgent groups or rebels; they want to classify groups in to a box, ignoring the fact that they do often commit different forms of political violence.18 'Terrorist' acts already have names and definitions. Murder is murder whether committed for hatred of a person, personal gain through ability to steal any goods or money a person has, or to instil fear in a segment of a population to coerce that segment to do something that they would not otherwise do.

While assassinations, certain types of property damage and other acts are intended to 'cause fear' and bring about a change in policy of a government (or other political/ideological/religious/etc. aim), there is not an attack on civilians.

A possible definition

An act of violence or the threat of such against a non-combatant/civilian/innocent target (according to the actor) to coerce an audience for political, religious, ideological, social, non-'personal' goals.

This definition includes the key characteristics, violence or the threat of, civilian/non-combatant target, an audience (that may or may not be the same as the target) that is intended to be coerced, for political etc. goals.

Clarification of definition

As was mentioned in the discussion surrounding what a working definition is, a definition should not shift the definitional problem onto another word. As such each possible 'problem' word in the above definition will be examined and explained. The first is 'violence', violence is physical assault on a person or person's body, threat of violence is propaganda, or other means to threaten violence. It does not include simple acts of property damage that are not meant to threaten violence or coerce. If it is widened to property possible problems arise such as if certain graffiti could be include (such as that written on a Sydney wall after 2004 Federal Election, "If you voted Liberal...I will hunt you down....and KILL YOU...I don't know where you live but I'm very good @ research."19). Within threat of violence this would be accepted however (but for other reasons this should not be considered terrorism). Another possible problem area is 'non-combatant/civilian/innocent', ultimately the target has to be view by the 'terrorist' themselves as a 'non-combatant/civilian/innocent'. Some might consider politicians to be non-innocent, and thus legitimate targets and attacks on them as non-terrorist acts.

The goal has to be of a nature that is political, religious or otherwise ideological or social. An act motivated by personal gain is not terrorism; again this has to be seen from the point of view of the actor.

Types of Political Violence

Terrorism is a contested concept that is often confused with other forms of political violence. For example, political assassination is sometimes called terrorism, and sometimes it is not. The following table distinguishes between state and non-state actors in the types of political violence each can commit. For the state, these acts can occur with the the state, or in or against another state.

Non-state actors Actual terrorist attacks (as defined) Supporting (criminal) 'terrorist' acts (acts not intended to cause fear or terror, but to facilitate future actions, such as bank robbery or arms depot robbery) Acts against state CNCNI Acts against non-state CNCNI
State actors Actual terrorist attacks (as defined) Acts against state CNCNI Acts against non-state CNCNI Acts by 'sponsored' groups of the above types

There are a number of different acts that are not terrorist acts as defined above. However it is necessary to mention them as they are often either confused or conflated with 'terrorist' acts. Specifically acts that are committed against state CNCNI (police, military etc.), such as political assassination or against non-state CNCNI (guerrilla's or other groups). Acts by 'terrorist' groups that are used to facilitate future 'terrorist' acts, such as bank robberies, are not terrorist acts in themselves as they are not intended to cause fear, though they could be combined with acts that are intended to cause fear, such as the killing of the bank staff and customers. Even in situations of armed conflict, violence against civilians is 'illegal'.


It is clear that with so many definitions of terrorism around it may seem hard to find one that fits all peoples needs, this is primarily because the definition of terrorism is often one that changes depending on the politics of the time. The problems of creating a working definition are many; however, the definition proposed fits the characteristics given. It is usable, not too broad, and ignores the actor and includes the aspects that a definition needs to differentiate 'terrorist' acts from other 'criminal' acts. It also addresses issues brought up in problems of usage section.


Burton, Anthony M.. Urban Terrorism - Theory, Practice & Response. London: Leo Cooper, 1975

CIA 'Terrorism FAQs' (accessed 24/03/2006)

Cockburn, Alexander. 'There Are No Innocents', (25/10/2004) (accessed 28/4/2006)

Constitutional Rights Foundation 'America Responds to Terrorism - What Is Terrorism?' (accessed 25/04/2006)

Commonwealth of Australia. Protecting Australia - Against Terrorism. Barton, ACT: The Department of the Prime Minister and Cabinet, 2004

Economic Analytical Unit (Australian Government Department of Foreign Affairs and Trade). Costs of Terrorism and the Benefits of Working Together. Barton, ACT: 2003

Hocking, Jenny. Beyond Terrorism - The Development of the Australian Security State. St Leonards, Australia: Allen & Unwin, 1993

Merari, Ariel. 'Terrorism as a Strategy of Insurgency', Terrorism and Political Violence 5, no. 4 Winter 1993

Primoratz, Igor. 'What is Terrorism', Journal of Applied Philosophy 7, no.3 1990

Santos Jr, Soliman M., 'Wanted: A legal definition of terrorism', (11/09/2002) (accessed 03/05/2006)

'DoD News Briefing with Lt. Gen. Renuart at the Pentagon' (accessed 30/4/2006)

'The Criminology of Terrorism: History, Law, Definitions, Typologies', (accessed 03/05/2006)

'What is Terrorism Defining Terrorism', About Inc, (accessed 24/03/2006) (accessed 30/4/2006) (accessed 30/4/2006)


Considering Its Long History and Current Prominence, Why Is It So Difficult to Define Terrorism?

The Global Terrorism Index calculates that around 64,000 people were killed by acts of terrorism between the years 2002-2011.  This is a startling illustration of how “terrorism has become one of the most pressing political problems during the last half-century” (Whittaker, 2007:vii)[1]. Yet academics, policy makers, and law enforcement officials alike have so far failed to establish a cohesive and unanimous definition of terrorism. This essay will consider the reasons for this, addressing the contested, divisive, and provocative nature of terrorism, and the changing nature of the phenomenon. Existing definitions will be considered, and common definitional elements examined. It will be contested that a universally accepted definition is likely to remain elusive, due to the complex and varied demands placed on definitions by the wide range of relevant interested parties. Legal bodies, academics, states, international bodies, and policy makers have competing interests and viewpoints, and the attempt to craft a definition which satisfies these parties, yet remains concise enough to be practical, is argued to be a futile endeavour and one which detracts from the overall attempt to counter the threat of terrorism.

Why Bother?

In order to enter into this debate, it is first necessary to consider the attempt to form a concrete definition of terrorism itself. It could be argued that the multitude of discussions on the subject amount to little more than disagreement over the use of language, leading to the important question: why bother? Asking this question is essential in order to uncover the motives behind and purpose for the desired definition, as well as to ensure that this pursuit is of more substantive value than simple semantics (Martin, 2010:9).

Definitions are vital to academic inquiry. As a building block of theory and empirical investigation, a definition informs the subject, scope and direction of study. The “classification of the phenomena that fall under this general category is an essential first step of research” (Chaliand and Blin, 2007:13). This is crucial, as theory and empirical investigation directly influence the wider discourse and knowledge of terrorism, as well as the attempt to obviate its threat. “Definitions of terrorism determine how research is conceptualized, executed, and employed in public policy”, and not simply within the academic world (Papacharissi and De Fatima Oliveira, 2008:55).

Definition is also of particular relevance to data collection, as incident and mortality rates vary wildly depending on the specifics of the definition employed. It has been claimed that without definition “there can be no uniform data collection and no responsible theory building on terrorism” (Schmid and Jongman, 1988:3). Indeed, the Global Terrorism Database details the difficulties in collating data on terrorism without a conclusive definition, and thus aims to produce “a data set that is useful to as many interested users as possible” in an attempt to overcome these problems[2]. As will be shown, there are numerous definitional elements which cause significant controversy within this debate, and when assessing incidents of terrorism the inclusion or exclusion of these from data collection has an immeasurable effect on the results obtained.

The need for valid definition is, then, certainly not confined to the academic sphere. The lack of clear definition also has real and serious consequences on international efforts to counter the terrorist threat, as “states cannot adequately counteract a phenomenon that they absolutely agree must be eliminated as long as they fundamentally disagree on its very definition” (Zeidan, 2005:217). As will be discussed, one of the complications which arises when attempting to form a definition lies in the mainly pejorative contemporary usage of the term. States are aware that ‘terrorism’ is a destructive force which needs to be prevented and constrained, but are unclear as to what precisely is or is not terrorism. As a result, the methods and approaches designed to neutralise the threat can be haphazard, inconsistent, and inexact, when certain acts are inconsistently labelled as terrorist or otherwise.

This demonstrates how “wrong definitions lead to wrong counter strategies” (Mackinlay, 2005). Indeed, regarding the catastrophic terrorist attacks in the United States on September 11 2001, states were unclear as to the exact nature of terrorism, and thus as to how to adequately respond to its threat. As such, there were many who defined and attempted to counter terrorism in diverse and conflicting ways, leading to a lack of international cooperation and cohesion. One view is that this “absence of an internationally accepted definition of terrorism has led to international lawlessness and unilateral vigilantism” (Acharya, 2008:678). It can thus be seen that definitions have far reaching effects and perform a crucial role within wider international politics, law and counter-terrorism strategy, and the debate surrounding this requires further investigation.

Common Definitional Elements

One major hindrance in attempting to form a single definition is the sheer volume and diversity of those which have been offered. Many authors have attempted to solve this problem by analysing the huge range of existing definitions and identifying the commonalities between them. Dershowitz, for example, suggests that definitions ordinarily consist of factors that fall within five categories: the nature of the group; the nature of the targets and victims; the means; the goals; and the mechanisms for achieving goals (Dershowitz, 2002:230). These frames provide broad groupings for analyses of both existing and possible definitions, and will be instructive in the following discussion.

Similarly, Schmid and Jongman conducted a significant and illuminating study, collating information from over 100 definitions and from this, offering a list of common elements. They found that there were 22 common elements, of which the most frequently presented were ‘violence’, ‘force’, ‘political’, and ‘fear, terror emphasized’ and ‘threat’ (Schmid and Jongman,1988:5). They claimed that on average “authors used eight categories to define terrorism” (Schmid and Jongman, 1988:6). This study provided an informative insight into the academic usage of definitions of terrorism, yet, as will be considered, did not conclude with the provision of a practical or universal definition itself.

Recently Weinberg et al have built upon this study where “the 22 ‘definitional elements’ of which Schmid’s definition is composed are compared to the frequency with which they appear in the professional journals” (Weinberg et al., 2004:777). The authors examined 73 definitions from a number of prestigious journals and finding that the most commonly employed elements were very similar, being: “Violence, force” “Political” and “Threat” (Weinberg et al., 2004:781). Using the analytical frames posited by Dershowitz, coupled with the definitional elements proposed here, will reinforce the examination of existing definitions that follows.

Existing Definitions: In Brief

To attempt to collate here the vast array of definitions proposed within the innumerate discourses, documents and studies on the subject is an unrealistic aim, and would dilute this discussion. It is however, important to consider some existing and influential definitions to explore these common themes and definitional components in the attempt to discover why firm definition remains unattainable.

Whilst “dictionary definitions are of little help” to wider discourse and practical usage, as a starting point of discussion they give insight into how the term is generally accepted within everyday society (Hoffman, 2006:2). The Oxford English Dictionary defines terrorism as “the unofficial or unauthorized use of violence and intimidation in the pursuit of political aims” (Stevenson, 2010). Interestingly, this definition does not consider the nature of the perpetrators, nor the means or mechanisms of achieving their goals. It also does not mention the use of threat of violence, specify who the targets are, or what the aims could be beyond their political nature. As such, whilst this definition may be simple and useful for basic introduction, when it is scrutinised further the sheer volume of absent elements renders it impractical and uninformative.

Bruce Hoffman, an eminent theorist within the study of terrorism, proposed the following definition: “Terrorism is thus violence – or equally important, the threat of violence- used and directed in pursuit of, or in service of, a political aim” (Hoffman, 2006:3). Similarly, this definition covers violence and political aims, but does not mention either who the perpetrators of the act are, or the intended victims or targets. It does however consider the significant element of threat of violence, implying that actual harm is not a necessary condition and the threat of harm itself is a sufficient indicator of a terrorist act. This has great consequences over the classification of terrorism, as a significantly larger proportion of incidents can be classed as terrorist if physical harm need not be a requirement, than would otherwise be the case.

Forst utilises a more substantial definition:

“Terrorism is the premeditated and unlawful use of violence against a non combatant population or target having symbolic significance, with an aim of either inducing political change through intimidation and destabilization or destroying a population identified as an enemy” (Forst, 2009:5).

Here there is mention of intent, description of the targets, of motivations and of certain goals. It highlights planning and legal elements of terrorism and places emphasis on the significance of the targets. Whilst this definition then perhaps could be seen to be more inclusive, it does neglect to define if terrorists are state or non-state actors, and to reference the use of threat of force. This is the first definition to be examined which makes reference to ‘intimidation’ of targets, which is a component of the psychological consequences of terrorism. Fear and psychological effects fall within the bracket of ‘terror’, which would appear to be a self-evident and crucial component of terrorism, but one which is in fact frequently lacking from many definitions.

Practical Definitions

Problems of definition are not limited to academic discourse.  In order to give a fuller picture of the variety and diversity of definitions currently in use beyond the academic sphere, official examples will now be considered. It has been suggested that “official definitions of terrorism are fairly similar”, however no one definition is universally accepted (Chaliand and Blin, 2007:14). Official definitions are used for specific purposes, often to dictate legal boundaries of the issue, to pursue and prosecute individuals involved in terrorism, or to form a basis for policy and political directives. In light of this, it is perhaps unsurprising that working definitions for these parties place a greater emphasis on the perpetrators of the act and their motives than academic definitions. Overall, official definitions commonly involve “three common elements…1) the use of violence; 2) political objectives; and 3) the intention of sowing fear in a target population” (Chaliand and Blin, 2007:14).

For instance, the CIA currently employs the following as its working definition: “The term ‘terrorism’ means premeditated, political motivated violence perpetrated against non-combatant targets by subnational groups or clandestine agents”[3]. Congruently, the FBI defines terrorism as “the unlawful use of force or violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof in furtherance of political or social objectives”[4]. The latter is the first definition to consider ‘property’ or damage to anything other than citizens or peoples. It also bears a remarkable resemblance to that used by the Department of Defence:

“the unlawful use of violence or threat of violence to instil fear and coerce governments or societies. Terrorism is often motivated by religious, political, or other ideological beliefs and committed in the pursuit of goals that are usually political”[5].

Interestingly this definition specifically considers the religious or ideological motivations of terrorists, unlike those examined previously.

The British Security Service (MI5) openly communicates the contested nature terrorism as a concept and, as such, posits a set of examples of what the terrorist threat encompasses in an attempt to provide an overview of the concept. For practical use, it also employs the definition proposed by the Terrorism Act, 2000 which defines terrorism as:

“the use or threat of action designed to influence the government or an international governmental organisation or to intimidate the public, or a section of the public; made for the purposes of advancing a political, religious, racial or ideological cause; and it involves or causes: serious violence against a person; serious damage to a property; a threat to a person’s life; a serious risk to the health and safety of the public; or serious interference with or disruption to an electronic system”[6].

Noteworthy here are the references to property, health and safety and electronic systems, as well as the inclusion of racial alongside religious and ideological motivations. This perhaps, reflects the nature of previous terrorist incidents that have occurred in Britain, or a strategic inclination towards classing certain matters (such as electronic systems and cyber-terrorism) as acts, or motivations of acts, to be officially classed as terrorism.

As mentioned, the Global Terrorism Database is a project which seeks to collate all records of terrorist incidents worldwide which uses:

“the threatened or actual use of illegal force and violence by a non-state actor to attain a political, economic, religious, or social goal through fear, coercion, or intimidation”

as its criteria[7]. As it can be seen, this definition is considerably more explicit with regards to the perpetrators of a terrorist act and their motivations. The specific mention of terrorists as ‘non-state actor’ is a critical inclusion which will be explored in detail later in this discussion. A potential limitation of this definition is that by specifically mentioning a list of valid motivations, it automatically excludes others. The mention of ‘illegal’ is also an important element, and one which is not frequently explicitly mentioned. This is due in part to the transatlantic nature of much contemporary terrorism which stands in tension with the finite national boundaries which usually dictate legal jurisdiction and precedence.

These are but a few examples and there are innumerate existing definitions of terrorism, both within academic discourse and beyond. There are many differences between these which are valid and important, and represent the diversity of the authors, purpose and fields of study for which definitions are created and employed. However, these differences also represent one of the fundamental obstacles in the effort to formulate a universal and accepted definition of terrorism.

Size Matters

Another major obstacle is that the drive to produce a comprehensive and inclusive definition can lead to a tendency towards overly lengthy and complex definitions. Whilst long definitions can contain more information and explicitly cover a larger range of aspects of terrorism, they can also encounter difficulties comparable to those faced by more succinct versions. As such, Schmid and Jongman present the following consensus definition in their formative review guide on the subject which begins: “Terrorism is a method of combat in which random or symbolic victims serve as an instrumental target of violence” and runs to over 170 words. Remarkably, this definition, whilst addressing the topic of intended targets in a very comprehensive manner, does not in fact consider who perpetrates the act, and does not consider a political dimension to their motivation or aims. Indeed it contains only 16 of the 22 definitional elements the authors identified from commonly used definitions, as discussed earlier. This suggests that even as an attempt is made to cover every potential constituent of terrorism, it is inevitable that a subjective claim will be made for the inclusion or exclusion of a certain factor by an interested party. The absence of a key element also becomes very apparent in a definition which has attempted to cover all possible features of terrorism.

Furthermore, long and wide-ranging definitions are severely limited in terms of practical use. The above consensus definition was, for example, too long to reproduce fully within this discussion, as it would be for official documentation, legal prose or concise empirical study. Practical use is an important consideration when attempting to craft most forms of definitions, and it is contended that there is a need for balance between inclusion and practicality. The authors of the above recognise this, suggesting that a “simple definition is unquestionably preferable to a wordy one, yet the price of parsimony should not be a lack of precision” (Schmid and Jongman, 1988:4).

The importance of the length and inclusivity of a definition is well framed by an understanding of Satori’s ‘ladder of abstraction’ theory. This depicts how a definition or concept with few elements is open to abstraction, explaining how a short definition allows for a wide range of acts to be included under the label of terrorism (Sartori, 1970). In comparison, definitions which include a greater number of elements require less abstraction, but cover only what is explicitly mentioned. Whilst employing a short definition could be seen to be “the line of least resistance”, it can unfortunately lead to what Sartori termed as “conceptual stretching” (Sartori, 1970:57). Conceptual stretching is where a concept, or in this case a definition, is stretched to include too large a range of issues, causing it to become overextended and to lose meaning. As such, whilst a concise definition may permit a large range of acts to be classified as terrorism, it can lead to the term losing relevance and significance. Certainly, this need to balance length and inclusivity whilst retaining conceptual rigidity and meaning, represents one of the greatest impediments to achieving a firm and unanimous definition.

History and Change

Another critical obstruction is to be found in the long and complex nature of the history of terrorism itself. The term has been dated to the French Revolution, but violent or threatening acts of the kind associated with a modern understanding of ‘terrorism’ have occurred throughout history (Hoffman, 2006:3). Not only is terrorism “as old as warfare itself”, but its character has changed frequently and substantially over its lifespan (Chaliand and Blin, 2007:5). The dynamism and transformative quality of terrorism makes the process of defining it extremely difficult. While a certain definition could apply satisfactorily to an act of terrorism from the 18th Century, it may be wholly inappropriate as a label for an act carried out in the recent past. It has therefore been argued that “the single greatest problem with defining terrorism…is its ability to evolve”, and it is certainly an critical problem (Buros, 2011:1).

The changing nature of terrorism is both an important and divisive issue. Where many would suggest that over time there have been changes in many aspects of terrorism, including “changes in concepts, techniques, locations, incidence, scale and organisation”, some extend this contention further (Whittaker, 2007:viii). Laqueur thus argued that terrorism is fundamentally different in the modern age; that “there has been a radical transformation, if not a revolution, in the character of terrorism” (Laqueur, 1999:4). Such a dramatic change in the nature of terrorism from that which occurred historically, and the assertion of the existence of a ‘new’ form of terrorism would aid in the understanding of the struggle for definition if it did exist. However, this standpoint has been treated critically, with opponents claiming “there is little that is new in the new terrorism” (Tucker, 2001:1). Crucially, this criticism is directed toward the suggestion that terrorism today is fundamentally and substantially different from its historical roots, not to a claim that it has changed in certain respects. Thus, it should be considered that whilst “terrorism…is changing all the time” to some degree, it retains a number of essential characteristics and has not radically transformed (Whittaker, 2007:34). This tension between the changes that have occurred in the nature of terrorism over time, and the consistency of the concept, represents another major difficulty in realising a fixed definition that retains relevance and applicability over time.


The negative emotional and moral overtones of terrorism also represent a “major hindrance in the way of achieving a widely accepted definition” (Chaliand and Blin, 2007:12). The terrorist act naturally instils a certain fear and terror in the population. Its prominence in media over recent decades, particularly in the West, has also created a persistent unrest and loaded the term with emotional connotations for the general public. These connotations have been replicated within both global politics and academia, and it could be said that today “the only universally accepted attribute of the term ‘terrorism’ is that it is pejorative” (Richardson, 2006:19). Traditionally, in fact, terrorism had positive overtones, and certainly was not subject to such a unified abhorrence (Hoffman, 2006).

The negativity with which terrorism is associated explains various aspects of the failure to form a definition. Firstly, it has been suggested that there exists “an implicit definition of terrorism as ‘violence of which we do not approve’” (Schmid and Jongman, 1988:3). This characterisation of any unacceptable forms of violence as terrorism complicates the issue and adds to the confusion over the terms’ boundaries and functions, and is a further example of Sartori’s conceptual stretching. The labelling of general violence as terrorism weakens the term’s meaning and makes the identification of terrorist acts far more difficult. General negativity also dilutes discussions over definition, requiring authors to make “convoluted semantic obfuscations to sidestep terrorism’s pejorative overtones” (Hoffman, 2006:21). This relates to the earlier question of whether the dispute over definition is simply due to semantics and suggests that, whilst the quest has real and important value, that authors are forced to enter into superficial debates in order to circumvent these negative connotations.

The State as Terrorist

The role of the state and non-state actors in definitions of terrorism is also of great importance, and presents another major challenge to the understanding, labelling and definition of the concept. As noted earlier, few of the examined definitions considered the perpetrators of terrorist acts and their position as either state or non-state actors. This is a crucial issue for a number of reasons. It has been traditionally understood that “a state is a human community that (successfully) claims the monopoly of the legitimate use of physical force” (Weber et al., 1946:77). This understanding has informed not only political philosophy, but also wider academia, governmental policy, and, indeed, law. Here then,

“many would insinuate the use of military force as a legitimate use of power, whereas any sort of non-military use of force or violence can be considered a form of terrorism” (Weinberger, 2003:65)

Discounting the actions of states from definitions of terrorism is not, however, universally accepted. Whilst, “according to many definitions of terrorism, only groups that are not part of the official apparatus of the state can commit terrorism”, many argue for the inclusion of state violence within definitions of terrorism (Dershowitz, 2002:4). States have, throughout the ages, enacted violence of far greater a destructive and lethal scale than carried out by sub-state actors, and numerous authors are therefore uncomfortable with the tendency to discount states from classifications of terrorism (Buckley and Fawn, 2003:25). Nonetheless, one perception of terrorism requires that the perpetrators of the act be sub-state actors, meaning that “although states can terrorize, by definition they cannot be terrorists” (Cronin and Ludes, 2004:4). This mirrors the definitions provided by both the CIA and the Global Terrorism Database as considered earlier, along with many others. Considering that it is the state which is the highest instrument of political and social control within the international system, this may lead to an unease in the general public if the state disregards its own deeds from definitions of terrorism, yet chooses to persecute sub-state actors for similar actions (Wendt, 1992). The role of state and non-state actors is a crucial and contentious aspect of the debate surrounding definition, and one which is particularly divisive and problematic.


Legitimacy is a key aspect of this debate, with established understandings providing legitimacy to the state to commit acts of violence against other states and non-state groups or individuals. It has been suggested that “terrorism is a fight over legitimacy between the terrorist group and the state” (Masters and Hoen, 2012:343). So, whilst states may hold the right to engage in acts of violence and to dismiss claims that their actions are tantamount to terrorism, they simultaneously identify and accuse sub-state actors of terrorism when carrying out similar violence. This discrepancy presents a major barrier in theorising, conceptualising, defining and countering terrorism globally.

It is also a fallacy which holds considerable weight in the modern political world, although it has faced criticism from two separate angles. The first of which is a claimed falsification in the understanding of legitimacy. Hoffman argues that the Weberian concept that the state holds a legitimate monopoly on violence is a misnomer, and that “even when violence is unavoidable it is never legitimate”  (Hoffman, 2003:535). This suggests that whilst states do on occasion have cause to carry out violence to protect their sovereignty and citizens, this violence is never legitimate. A second angle suggests that the label of terrorism could be seen as “a semantic device by which the state and its agents divert attention from their own crimes” (Weinberg et al., 2004:786). This suggests then, that when states label and criminalise groups and individuals as terrorists, and exclude themselves from definitions of terrorism, they are to some degree attempting to conceal their actions or bestow them with unsubstantiated legitimacy. Both viewpoints, whilst valid and valuable in other contexts, serve in this respect to complicate the issue of definition.

The role of legitimacy in definitional terms is not confined to discussions of state versus non-state actors; it is also crucial with regards to terrorists themselves. Within discussions of terrorism, the aphorism ‘one man’s terrorist is another’s freedom fighter’ is all too frequently employed. However, it does highlight another relevant definitional problem, which builds on both the discussions concerning negative connotations of the term and the role of legitimacy. It is claimed that “the distinction between terrorists and freedom fighters is frequently blurred across political regimes” (Papacharissi and De Fatima Oliveira, 2008:54). This implies that terrorists and freedom fighters are intrinsically different in some way and should be treated so. Freedom fighters are granted some form of validity, or indeed legitimacy, for their actions, whereas terrorists are not. Freedom fighters, by trying to free themselves from oppressive rule by undemocratic regimes are, in this perspective, principally distinguished from terrorists, who use violence in an attempt to bring about political reform against an organised and legitimate state (Richardson, 2006).

Similar disputations arise when groups that have previously employed terrorism, gain political, social or legal legitimacy, and become recognised as valid political actors (Acharya, 2008:656). Many groups have followed this pattern, such as the IRA in Northern Ireland, the PLO in Palestine, and, to some extent, Hezbollah in Lebanon. Transformations such as these could be seen to add to the problems of definition, unless it is acknowledged that “the focus is not or should not be whether a group is a terrorist group, but rather what activities or actions constitute terrorism” (Acharya, 2008:656). In the light of this, all of the above groups carried out terrorist activities even when regarded as legitimate actors. Therefore, this need not affect attempts to formulate a valid definition if the focus is placed on the acts themselves, and not on the nature of a particular group. This would mean that the importance is not placed on the labelling of certain groups as terrorists, but instead upon individual acts of terrorism. Such a shift in focus would also aid in the attempt to differentiate between freedom fighters and terrorists, in that freedom fighters would be seen to be terrorists when and if they employ acts of terrorism.

Aims of Definition

There are clearly a wide range of issues which complicate the attempt to form a conclusive definition of terrorism.  One of the most significant, is the range of competing requirements placed on a definition from the various relevant parties. This discussion has considered definitions from law enforcement bodies, statute, academic research, and data collection enterprises, all of which have rival interests in, and purposes for, a definition of terrorism. These definitions only represent a miniscule percentage of those which have been proposed by innumerate different actors, all with varied expectations of what a definition should include and how it should be employed.

Schmid and Jongman argue that there are four main arenas of discussion in which an attempt is made to find a definition of terrorism: the academic arena; state statements about terrorism (including laws); public debate (that is, media interpretation and labelling); and discussions by potential terrorists or groups in opposition to established states (Schmid and Jongman, 1988).  These groups have very different aims and focuses, and employ definitions of terrorism in conflicting manners. Whilst this is a constructive insight into the debate as it highlights the diversity of interested parties, Weinberg et al highlight that these categories are not mutually exclusive and as such, are limited in practical use for this discussion. What is clear is that when so many “conflicting demands are made on the definition”, consensus is unlikely to be reached (Schmid and Jongman, 1988:11).

Another pertinent concern surrounding the generation and use of definitions relates to who is involved in the pursuit itself. For instance, a Western political official may have quite different cultural, social, and legal expectations of a definition of terrorism than a member of an active terrorist group. If both were tasked with crafting a definition, it is not inconceivable that they would produce wildly different classifications. Thus, it is important to recognise the relevance of the question: “who is defining the term and where does s/he come from?” (Weinberg et al., 2004:783). Indeed, as has been briefly mentioned, the media has considerable influence over the understanding of terrorism within the general public and beyond.  Thus, a journalist would likely produce a vastly different definition than that of a policy maker. The possible biases and assumptions inherent in the views and perspectives of those attempting to form definitions are, then, significant, and should be explicitly considered.

Why Bother, Again?

The endeavour to form a definition is evidently problematic, but it could be contended that the fight against terrorism in the wider world is not substantially hindered by this lack of agreement. Indeed “the task of outlawing terrorism has been relatively easier than reaching an international agreement about the criteria in defining terrorism” (Weinberger, 2003:77). In this way, the problems and obstacles as discussed here represent only a minor hindrance to the actual pursuit of countering terrorism, and “the construction of a legal mechanism that can be used to suppress terrorism has proceeded despite this failure” (Levitt,1986:115). Whilst states, law enforcement groups, and international bodies may still be unable to precisely and unanimously define terrorism, they remain relatively well equipped in the attempt to prevent and constrain its threat.


It is therefore abundantly clear that the attempt to form a universal and comprehensive definition of terrorism which balances practicality with inclusivity has not yet succeeded.  There are argued to be too many different interested parties with vastly competing interests, biases, and requirements to be able to craft a universal definition. Also, considering that terrorism has such a long and complex history, frequently adapting and changing at least to some degree, it is contended that even if a valid definition were to be created, it would be unlikely to retain unilateral support into the future.

What is needed is a shift in focus from this futile general attempt to create an overarching and universal definition, towards crafting appropriate definitions for specific purposes, such as the official definitions used by the law enforcement bodies and governments as considered earlier. In this way, a number of definitions could be created which satisfy the particular interests and needs of certain groups or parties, without the need for universal or unanimous acceptance. This lack of consensus, then, need not impede the attempts to counter terrorism itself, if more limited and purposeful definitions are employed. So, whilst it is suggested that the attempt to form a valid, cohesive and comprehensive definition which is practical and yet satisfies the huge range of relevant parties is likely unattainable, it is also somewhat misguided.


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[1] Data retrieved from: Accessed 17/4/2013

[2] Accessed 17/4/2013

[3] Definition retrieved from: Accessed 29/3/12

[4] Definition retrieved from: Accessed 18/4/12

[5] Definition retrieved from:  Accessed 20/4/2013

[6] Definition retrieved from: Accessed 21/4/2013

[7] Definition retrieved from:  Accessed 17/4/2013

Written by: Catherine Goodall
Written at: The University of Nottingham
Written for: Mr Andrew Mumford
Date written: May 2013