Definition of terrorism

There is no legal or scientific consensus on the definition of terrorism. Various legal systems and government agencies use different definitions of terrorism, and governments have been reluctant to formulate an agreed-upon legally-binding definition. Difficulties arise from the fact that the term has become politically and emotionally charged. A simple definition proposed to the United Nations Commission on Crime Prevention and Criminal Justice by terrorism studies scholar Alex P. Schmid in 1992, based on the already internationally accepted definition of war crimes, as "peacetime equivalents of war crimes", was not accepted.
Scholars have worked on creating various academic definitions, reaching a consensus definition published by Schmid and A. J. Jongman in 1988, with a longer revised version published by Schmid in 2011, some years after he had written that "the price for consensus led to a reduction of complexity". The Cambridge History of Terrorism, however, states that Schmid's "consensus" resembles an intersection of definitions, rather than a bona fide consensus.
The United Nations General Assembly condemned terrorist acts by using the following political description of terrorism in December 1994 :

Criminal acts intended or calculated to provoke a state of terror in the general public, a group of persons or particular persons for political purposes are in any circumstance unjustifiable, whatever the considerations of a political, philosophical, ideological, racial, ethnic, religious or any other nature that may be invoked to justify them.

Etymology

The term "terrorism" comes from French terrorisme, from, "great fear", "dread", related to the Latin verb terrere, "to frighten".
The French National Convention declared in September 1793 that "terror is the order of the day". The period 1793–94 is referred to as La Terreur. Maximilien Robespierre, a leader in the French Revolution proclaimed in 1794 that "Terror is nothing other than justice, prompt, severe, inflexible."
The Committee of Public Safety agents that enforced the policies of "The Terror" were referred to as "Terrorists". The word "terrorism" was first recorded in English-language dictionaries in 1798 as meaning "systematic use of terror as a policy".
Although the Reign of Terror was imposed by the French government, in modern times "terrorism" usually refers to the killing of people by non-governmental political activists for political reasons, often as a public statement. This meaning originated with Russian radicals in the 1870s. Sergey Nechayev, who founded the People's Reprisal in 1869, described himself as a "terrorist". German radicalist writer Johann Most helped popularize the modern sense of the word by dispensing "advice for terrorists" in the 1880s.
According to Myra Williamson : "The meaning of 'terrorism' has undergone a transformation. During the reign of terror a regime or system of terrorism was used as an instrument of governance, wielded by a recently established revolutionary state against the enemies of the people. Now the term 'terrorism' is commonly used to describe terrorist acts committed by non-state or subnational entities against a state".

Notable definitions of terrorism

Definitions include:

"the deliberate killing of innocent people, at random, to spread fear through a whole population and force the hand of its political leaders".
"the organized use of violence to attack non-combatants or their property for political purposes".
"the deliberate use of violence, or threat of its use, against innocent people, with the aim of intimidating some other people into a course of action they otherwise would not take".
"the use of force or violence or the threat of force or violence to change the behavior of society as a whole through the causation of fear and the targeting of specific parts of society in order to affect the entire society".
"The premeditated use or threat to use violence by individuals or subnational groups to obtain a political or social objective through the intimidation of a large audience beyond that of the immediate victims".
"a doctrine about the presumed effectiveness of a special form or tactic of fear-generating, coercive political violence... a conspiratorial practice of calculated, demonstrative, direct violent action without legal or moral restraints, targeting mainly civilians and non-combatants, performed for its propagandistic and psychological effects on various audiences and conflict parties".

Bruce Hoffman notes that terrorism is "ineluctably about power".

General criteria

Terrorism has been described as:

The use of violence or of the threat of violence in the pursuit of political objectives
Acts committed by non-state actors
The intentional use of lethal force against civilians, and/or destructive force against civilian areas, buildings or infrastructure.
Acts reaching more than the immediate target victims and also directed at targets consisting of a larger spectrum of society
Both mala prohibita and mala in se

Definitions of terrorism typically emphasize one or more of the following features:

Its effect of extreme fear
Whether it targeted the state from within
Its strategic goals
Its random or indiscriminate nature
Who it targeted
Whether it was planned and prepared in secret

The following criteria of violence or threat of violence usually fall outside of the definition of terrorism:

Wartime or peacetime acts of violence committed by a nation state against another nation state regardless of legality or illegality and are carried out by properly uniformed forces or legal combatants of such nation states
Reasonable acts of self-defense, such as the use of force to kill, apprehend, or punish criminals who pose a threat to the lives of humans or property
Legitimate targets in war, such as enemy combatants and strategic infrastructure that form an integral part of the enemy's war effort such as defense industries and ports
Collateral damage, including the infliction of incidental damage to non-combatant targets during an attack on or attempting to attack legitimate targets in war

Scholar Ken Duncan argues the term terrorism has generally been used to describe violence by non-state actors rather than government violence since the 19th-century Anarchist Movement.

In international law

The need to define terrorism in international criminal law

Schmid summarised many sources when he wrote: "It is widely agreed that international terrorism can only be fought by international cooperation". If states do not agree on what constitutes terrorism, the chances of cooperation between countries is reduced; for example, agreement is needed so that extradition is possible.
Ben Saul has noted : "A combination of pragmatic and principled arguments supports the case for defining terrorism in international law". Reasons for why terrorism needs to be defined by the international community include the need to condemn violations to human rights; to protect the state and its constitutional order, which protects rights; to differentiate public and private violence; to ensure international peace and security, and "control the operation of mandatory Security Council measures since 2001".
Carlos Diaz-Paniagua, who coordinated the negotiations of the proposed United Nations Comprehensive Convention on International Terrorism, noted in 2008 the need to provide a precise definition of terrorist activities in international law: "Criminal law has three purposes: to declare that a conduct is forbidden, to prevent it, and to express society's condemnation for the wrongful acts. The symbolic, normative role of criminalization is of particular importance in the case of terrorism. The criminalization of terrorist acts expresses society's repugnance at them, invokes social censure and shame, and stigmatizes those who commit them. Moreover, by creating and reaffirming values, criminalization may serve, in the long run, as a deterrent to terrorism, as those values are internalized." Thus, international criminal law treaties that seek to prevent, condemn and punish terrorist activities, require precise definitions:
Saul noted in this sense that, missing a generally agreed, all-encompassing, definition of the term:

Obstacles to a comprehensive definition

There are many reasons for the failure to achieve universal consensus regarding the definition of terrorism, not least that it is such a "complex and multidimensional phenomenon". In addition, the term has been used broadly, to describe so many different incidents and events that scholar Louise Richardson has said that the term "has become so widely used in many contexts as to become almost meaningless". An analysis of 73 different definitions in 2004 came up with only five common elements, which excluded any reference to victims, fear/terror, motive, non-combatant targets or the criminal nature of the tactics used.
Historically, the dispute on the meaning of terrorism arose since the laws of war were first codified in 1899. The Martens Clause was introduced as a compromise wording for the dispute between the Great Powers who considered francs-tireurs to be unlawful combatants subject to execution on capture, and smaller states who maintained that they should be considered lawful combatants.
More recently the 1977 Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts, which applies in situations Article 1. Paragraph 4 "... in which peoples are fighting against colonial domination and alien occupation and against racist regimes...", contains many ambiguities that cloud the issue of who is or is not a legitimate combatant.
In a briefing paper for the Australian Parliament in 2002, Angus Martyn stated:

The international community has never succeeded in developing an accepted comprehensive definition of terrorism. During the 1970s and 1980s, the United Nations attempts to define the term floundered mainly due to differences of opinion between various members about the use of violence in the context of conflicts over national liberation and self-determination.

Diaz-Paniagua has noted that, to "create an effective legal regime against terrorism, it would be necessary to formulate a comprehensive definition of that crime that, on the one hand, provides the strongest moral condemnation to terrorist activities while, on the other hand, has enough precision to permit the prosecution of criminal activities without condemning acts that should be deemed to be legitimate". Nonetheless, due to major divergences at the international level on the question of the legitimacy of the use of violence for political purposes, either by states or by self-determination and revolutionary groups, this has not yet been possible." In this sense, M. Cherif Bassiouni notes:
Sami Zeidan, a diplomat and scholar, explained the political reasons underlying the current difficulties to define terrorism as follows :
In the same vein, Jason Burke, a British reporter who writes about radical Islamist activity, said:
The political and emotional connotation of the term "terrorism" makes difficult its use in legal discourse. In this sense, Saul notes that:
As scholar Bruce Hoffman has noted: "terrorism is a pejorative term. It is a word with intrinsically negative connotations that is generally applied to one's enemies and opponents, or to those with whom one disagrees and would otherwise prefer to ignore. Hence the decision to call someone or label some organization 'terrorist' becomes almost unavoidably subjective, depending largely on whether one sympathizes with or opposes the person/group/cause concerned. If one identifies with the victim of the violence, for example, then the act is terrorism. If, however, one identifies with the perpetrator, the violent act is regarded in a more sympathetic, if not positive light; and it is not terrorism." For this and for political reasons, many news sources avoid using this term, opting instead for less accusatory words like "bombers", "militants", etc.
The term has been depicted as carrying racist, xenophobic and ethnocentric connotations when used as an ethnic slur aimed at Arabs or Middle Easterners, or at someone of Arab or Greater Middle Eastern descent or when used by white supremacists.
These difficulties led Pamala Griset to conclude that: "the meaning of terrorism is embedded in a person's or nation's philosophy. Thus, the determination of the 'right' definition of terrorism is subjective".
While discussing the definitional and ethical difficulties of terrorism, philosopher Jenny Teichman argues that "it ought not to be impossible to find an agreed definition, and then ask whether one wants to condemn or applaud all or some of the things that fall under that description". Experts disagree on "whether terrorism is wrong by definition or just wrong as a matter of fact; they disagree about whether terrorism should be defined in terms of its aims, or its methods, or both, or neither; they disagree about whether states can perpetrate terrorism; they even disagree about the importance or otherwise of terror for a definition of terrorism".