What is terrorism?

Namur, October 15, 2023

The concept of terrorism is particularly sensitive when it is used to de-legitimize adversaries or opponents on the national and international stage in order to marginalize or even repress them [1]. The example of the Uighur separatists in Xinjiang is often cited because it implicates the Chinese government, but many other situations are similar [2]. Everyone can see how difficult it is to define terrorism outside the framework of the passions it generates through actions that are generally highly theatrical in order to have an impact that corresponds to its ultimate objectives. It is also quite classic to consider with one of its great specialists, the German-American historian Walter Z. Laqueur (1921-2018) that, given its diversity and the horror and fascination it inspires, defining terrorism and establishing a coherent theory of it would be an impossible task [3]. In fact, it is above all the notions of state terrorism and resistance or national liberation that pollute the academic and political efforts to base a definition on reason. Thus, we can follow Anthony Richards when he observes that viewing terrorism as a method rather than as inherent to any particular type of cause helps us to consider the phenomenon more objectively [4]. This method, as we know, consists of generating a psychological impact beyond the victims of the acts perpetrated. However, as the author, Professor of Law at the University of London, points out, the difficulty lies in showing the intention that is present or hidden behind the action taken [5].

So, we could try this definition inspired by the following reflections and the work of the French historian Jenny Raflik [6]: terrorism is a political project over a period, aimed at challenging the established order, attempting to bring it to an end and replacing it with a new order. To this end, it makes tactical use of transgressive violence, which, however, is presented and considered legitimate by the terrorist in the context of actuality.

That’s what we’re going to try to understand.

Photo Dreamstime – Aquarius83men

1. Two initial concerns

Returning to the issue of terrorism, I have two initial concerns. The first is that the issue is, of course, complex – more complex than is generally thought. It is far from being just a question of a few Arab countries and the Muslim religion. If I thought that was the case, I would have to stop writing now. Having studied Russian terrorism in Europe before the October Revolution as a historian, I know only too well that without a detailed knowledge of the language and culture, it is impossible to enter the mindset or networks, even retrospectively. This complexity must be considered, which is why I call my first approach The Road to Damascus, referring to the experience of the Apostle Paul of Tarsus. Like the former bounty hunter and persecutor of Christians, we have been blinded by the light of evidence, and we must pursue the truth with great humility if we are to regain a clear vision. This, of course, is the daily task of researchers and especially of foresighters. This idea was beautifully expressed by Michelangelo in the 16th century in a fresco in the Pauline Chapel in Rome and, closer to home, in a painting by Bertholet Flemalle in the 17th century in St Paul’s Cathedral in Liège (Wallonia). Incidentally, the New Testament is still relevant today: Jesus is said to have said, Go to Damascus, where it will be told you what to do. One thing is certain: contemporary interpretations are manifold…

My second initial concern is to point out that terrorism is not exempt from temporality, by which I mean the complex relationship of the present to both the past and the future. The public is regularly shocked by events that the media present as exceptional, unique or unprecedented. Yet we know that such events have occurred many times in the past, in one form or another, and that they are part of a long-standing trend and an already familiar pattern of development. For example, the accidental explosion of a bomb outside the Château de Villegas in Ganshoren, Brussels, at half past three on 23 February 1883, which killed its bearer, allowed the Belgian security services to partially uncover the network of the Narodovoletzi – the “bearers of the people’s will” of Odessa. It also allowed the historian who reconstructed the network to understand both how it worked and what motivated its members, to analyse how the anti-terrorist services viewed it, how they cooperated or did not cooperate, etc. This analysis is very useful for understanding and trying to explain what is happening today and what might happen tomorrow [7].


2. Some of the forms terrorism has taken in history

Temporality is based on the retrospective, or even – as we shall see – the retro-foresight. The retrospective is the basis of historicity that always subjective (or even intersubjective, as Edgar Morin would put it) connection we have with the past. Far from taking the past for granted, we are constantly revisiting it and finding there the questions we have about the present and, above all, the future. Is this not why the Italian historian Benedetto Croce (1866-1952) said that all history is contemporary?

I do not intend to recount the history of terrorism, or even of European terrorism, but it is certainly useful to keep in mind some of the forms it has taken in history – which is now beyond our power – to draw some conceptual or strategic lessons that we will need to face the future.

From the outset, temporality seems to be mixed with timelessness. The world-famous novel Alamut (1938) by the Slovenian writer Vladimir Bartol (Trieste, 1903 – Ljubljana, 1967) may be one of the keys to understanding the phenomenon of terrorism. On the one hand, it is inspired by the Ismaili sect and analyses the psychological traits of young fighters devoted to the cult of the Koran and raised with a fascination for duty and death that will allow them to enter paradise. Secondly, Alamut inspired the video game Assassin’s Creed, developed by Ubisoft Montreal for PlayStation3 and Xbox 360 in 2007 and for PC the following year. More than 100 million copies of the various entries in the series have been sold worldwide. Its influence has therefore been greater than an article in The Economist. The film realized in 2016 by the Australian director Justin Kurzel reinforced this messianic mythology whose formulas and principles are familiar: I divide mankind into two fundamentally different categories: a handful of people who understand reality and the huge majority who do not. Or again, Nothing is true; everything is permitted [8]. While researchers are aware of the importance of people’s worldviews in motivating individual or collective action, we must recognize that the frequency with which we now move between the real and the virtual world – not to mention our tendency to confuse the two – adds to the complexity of an issue such as terrorism.

Far from being the exclusive tool of cults, secret societies and resistance movements, terror is inherent in violence and war. In his Commentaries on the Gallic Wars, Julius Caesar recounts how the brilliance of his attacks – but also their brutality – both kept his friends loyal and, through fear, forced the wavering to accept offers of peace [9]. Experts in etymology and comparative linguistics know that variants of the Latin words terror and terrere have appeared in many forms over the centuries, long before the Terror proclaimed by the French National Assembly on 5 September 1793. We know of the terror inspired in us by the steppe peoples under Attila the Hun in the 5th century, the Mongol Genghis Khan in the 13th century and Tamerlane in the 14th century. The latter is known to have terrorized enemy cities and nations by building pyramids of severed heads, for example in Isfahan in 1387. But let us not jump to the conclusion that hell is other people. One of the field marshals at the head of the army of Maximilian of Bavaria’s Catholic League was Johann Tserclaes, Count of Tilly, who was sometimes said to be Walloon [10]. During a campaign against the Protestant Evangelical Union during the Thirty Years’ War, he seized the German city of Magdeburg on 25 May 1631, and permitted the slaughter of 20,000 people as well as the visitation of numerous other atrocities on the population in order to ensure the surrender of the neighbouring cities. The Marquis de Sourdis, in Richelieu’s service, did likewise at Chatillon-sur-Saône four years later. Many Belgian cities suffered similar treatment during the German invasion in the Great War, such as Dinant on the Meuse on 23 August 1914 (605 deaths). The Nanking Massacre in late 1937 and early 1938 probably claimed nearly 250,000 lives, and perhaps represented the pinnacle of this type of terrorism. And there are also civil wars, which can sometimes – whether in a revolutionary period or not – visit terror on the national population, as we have already mentioned regarding the French Revolution. Such circumstances legitimize the massacre by the citizens of the Republic’s enemies: this is what happened, for example, in Lyon on 14 December 1793, and perhaps too in Ankara on 15 July 2016.

In The Spirit of the Laws, Montesquieu used the term ‘terror’ in 1748 to refer to the principle of despotic government [11]. Long before him, in 1690, John Locke had stated in the first essay of his two Treatises on Government that ‘the magistrate’s sword [is] for a terror to evil doers, and by that terror to enforce men to observe the positive laws of the society’[12]. The use of the words ‘terrorism’ and ‘terrorists’ began to spread from 1794, first in the sense of a regime of political terror and its partisans, and then in the broader sense of the systematic use of violence for political purposes. Incidentally, ‘anti-terrorism’ and ‘anti-terrorist’ appear just one year later, in 1795 [13].

Of course, modern mechanized weaponry makes mass violence possible on an unprecedented scale. The bombing of Guernica, the historic capital of the Basque country, on 23 April 1937, notoriously served as a kind of rehearsal for what was to ensue during the Second World War. The bombing of Rotterdam by the Luftwaffe on 14 May 1940 was undoubtedly also an act of terrorism. It is difficult to exempt from this sombre list the massive German, British and American bombardments of civilian targets, and especially of cities, during this conflict. As Ariel Merari points out, the ultimatum leaflets that were air-dropped in these areas attest to the desire to terrorize the civilian population directly [14]. The Allied and German services that counted the number of victims of the bombing raids on Germany estimated the death toll at around 400,000, more than 10% of whom were prisoners of war or foreigners. The number of civilians killed by the bombing of Japan was around 900,000, higher than the number of Japanese soldiers killed in combat [15].

The Second World War also provides an interesting illustration of the ambivalence of the concepts of terrorism and resistance. A striking example is the Manouchian network, which was so well known that it was the subject of a propaganda poster distributed by the Vichy regime in 1944. The Missak Manouchian group, made up of resistance fighters of foreign origin, Jews and communists, became known for its attacks on German pilots and soldiers on leave. Its members, who described themselves as irregular sharpshooters and partisans (‘francs-tireurs et partisans’, FTP), were condemned to death and executed by the Germans in 1944 as ‘terrorists’, then honoured as members of the resistance by Charles de Gaulle’s Free France after the liberation [16]. The same view was taken of the members of the Irgun when they attacked the British headquarters at the King David Hotel in Jerusalem on 22 July 1946, causing 91 deaths and numerous injuries among the British officials there. Another example of the difficulty of defining the concept of terrorism is the so-called Battle of Algiers, fought by French parachute regiments during the decolonization period from January to October 1957. It is clear that the radical anti-terrorist measures taken by the French military had some success because they themselves terrorized the nationalist indigenous peoples and the settlers who sympathized with them.

The very disparate actions that have been mentioned reveal the different forms that terrorism can take, and a longer-term process in which we are situated, which debunks the notion that what is happening to this generation is unique, novel or unprecedented. Confining our attention to modern times, we can also count as part of this process the numerous attacks and actions of anarchists, nihilists, revolutionary socialists, fascists and others throughout the 19th and 20th centuries: they include the assassination of Tsar Alexander II (1881), of President Sadi Carnot (1894) and of Archduke Franz Ferdinand of Habsburg (1914), the Black September attacks at the Munich Olympics (1972), the actions of the Red Army Faction (Hanns-Martin Schleyer, 1977), the Red Brigade, Action directe and the Communist Combatant Cells, the bombing of Bologna railway station (2 August 1980), the attacks in Beirut against U.S. and French forces (23 October 1983), the killers of Brabant (28 deaths from 1983 to 1985), the attacks of the AIG such as the RER Line B bombing at Saint-Michel station in Paris on 28 July 1995, and that pivotal global moment on 11 September 2001 that has had so many repercussions for Europe.

This very incomplete inventory shows the diversity of forms that terrorism can assume [17]. It might have been expected to yield precise criteria for a general definition, but this is not in fact the case. As Ariel Merari shows, although terrorism may seem an immoral form of war, the profound collapse that the moral code of behaviour underwent in almost all wars on the part of all parties in the 20th century, including the targeting of civilians, shows that the difference between terrorism and other forms of war is one of interpretation [18].

If further demonstration of this relativity is required, take a look at the definition of ‘terrorisme’ in the French dictionary of Lachâtre in 1890. This was a popular dictionary, close to the labour movement. After recalling that the term refers to the reign of terror that reigned in France during part of the Revolution, Maurice Lachâtre added that terrorism is the most moving revolutionary era. He then defines a terrorist as a partisan, an agent of the system of terror, adding that the terrorists saved France [19].

What can we say other than that such comments on terrorism should make us humble?


3. Towards a definition of terrorism

It is conventional to begin discussions of terrorism by considering the difficulty of defining it in the scientific literature. We should avoid conflating it with all forms of political violence and ignoring state-sponsored forms of terrorism [20].

At a very early stage, however, in 1962, Raymond Aron made a decisive contribution by suggesting that ‘a terrorist action is referred to as such when its psychological effects are disproportionate to its purely physical results [21]. The various definitions offered by international organizations can help us understand this phenomenon. Thus, UN Resolution A/RES/54/110 of 2 February 2000 refers to criminal actions with political aims: 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 [22].

The 2021 NATO definition, taken from its English and French glossary, shares this idea of a political dimension: The unlawful use or threatened use of force or violence, instiling fear and terror, against individuals or property in an attempt to coerce or intimidate governments or societies, or to gain control over a population, to achieve political, religious or ideological objectives [23].

The Luxembourg Council of the European Union in 2002 identified an intent to seriously intimidate a population, or unduly compelling a Government or international organization to perform or abstain from performing any act, or seriously destabilizing or destroying the fundamental political, constitutional, economic or social structures of a country or an international organization [24], an idea often found in national legislation, such as the Belgian law of 19 December 2003. The French historian Jenny Raflik stresses the interest of the approach to the phenomenon taken by the Arab Convention on the Suppression of Terrorism, adopted in Cairo on 22 April 1998, which is both innovative in several respects yet includes limitations such as the possibility of excluding from the scope of terrorism struggles that could the declared legitimate [25]. The important exploratory work of the historian at the French Institute for Higher National Defence Studies led her to propose a definition that we endorse: terrorism is a political project over a period of time that aims to challenge the established order, to try to put a stop to it and/or to substitute a new order for it. To this end, it makes tactical use of transgressive violence, which, however, is presented and regarded as legitimate by the terrorist, in the context of actuality [26]. This definition seems highly relevant to us. First, because it objectifies terrorism and takes it seriously as a political project rather than as a deviation, which would undermine its importance and purposes. Next, because Jenny Raflik emphasises the use of transgressive violence as a means, together with the subjective element – the variance of perspective between perpetrator and victim. Finally, because this definition takes into account the temporality in which the tension between the immediate event and its far-reaching effects lies.


Five Considerations to Close the Paper but Not the Subject

1. Terrorism is not a recent phenomenon. It is part of a long-term development from antiquity to the present. It should be seen in temporality (relationships between past, present and future).

2. Terrorism is a complex issue that takes many forms and can be used by very different actors, individual or collective, private or public, who are inspired by a political project and, therefore, a strategic determination to act in order to maintain or change an existing situation. In defining terrorism, we should avoid conflating it with all forms of political violence and ignoring state-sponsored forms of terrorism.

3. The use of terror and terrorism against citizens is inherent in the political philosophy of our liberal societies, as understood in particular by John Locke and Montesquieu.

4. The legitimacy of this political project is subjective; its means are transgressive and intended to be reinforced by their psychological impact and media coverage.

5. Several examples of the evolution of relations between groups that were clearly seen as terrorists, with whom it seemed impossible to negotiate, show that this is not the case and that yesterday’s transgressive actions do not necessarily prevent people from sitting down to start fruitful negotiations. The development of relations between London and the IRA after the bloody events of the Second World War is interesting in this respect.

Once again, we can find reasons for hope in a landscape of despair. Provided we make the necessary efforts, based on reason and not passion.



Philippe Destatte


[1] A first and longer version of this paper has been written in the framework of the NATO Advanced Research Workshop, Identification of Potential Terrorists and Adversary Planning, Emerging Technologies and New Counter-Terror Strategies, CSRA, Falls Church VA, 25 July 2016, edited:  Ph. DESTATTE, Counter-Terrorism in Europe 2030; Managing Efficiency and Civil Rights, in Theodore J. GORDON e.a., Identification of Potential Terrorists and Adversary Planning, p. 87-105, NATO Science for Peace and Security Series – E: Human and Societal Dynamics, IOS Press, 2017. Philippe-Destatte_Counter-terrorism-Europe_NATO-IOS_2017

See also: Philippe DESTATTE, Elisabeta FLORESCU, Garry KESSLER, Hélène von REIBNITZ, Karlheinz STEINMÜLLER, Identifying Some Issues in the NATO Zone Through Trajectories About the Future of Terrorism and Counter-Terror Strategies, in Theodore J. GORDON e.a., Identification of Potential Terrorists and Adversary Planning, p. 16-24, NATO Science for Peace and Security Series – E: Human and Societal Dynamics, IOS Press, 2017.

[2] Ben SAUL, Defining Terrorism to protect Human Rights, in Deborah STAINES ed., Interrogating the War on Terror, Interdisciplinary Perspectives, p. 201-202, Newcastle, Cambridge Scholars Publishing, 2007.

[3] Walter LAQUEUR, Le terrorisme, p. 15, Paris, PuF, 1979. – W. LAQUEUR, Terrorism, London, Weidenfeld and Nicholson, 1977. – W. LAQUEUR, No End to War, Terrorism in the Twenty-First Century, p. 238, London, Continuum International, 2003.

[4] Anthony RICHARDS, Defining Terrorism, in Andrew SILKE ed., Routledge Handbook of Terrorism and Counterterrorism, p. 17, London & New York, Routledge, 2020. – A. RICHARDS, Conceptualizing Terrorism, Oxford University Press, 2015.

[5] Ibidem, p. 19.

[6] Jenny RAFLIK, Terrorisme et mondialisation, approches historiques, p. 24, Paris, Gallimard, 2016. – Terrorismes en France, Une histoire XIXe-XXIe siècles, Paris, CERF, 2023.

[7] Ph. DESTATTE, Contribution à l’histoire de l’émigration russe à la fin du XIXe siècle, 1881-1899, Mémoire présenté pour l’obtention du grade de Licencié en Histoire, Liège, Université de Liège, Année académique 1978-1979, 240 p. – Ph. DESTATTE, Sûreté publique et Okhrana, Les Foyers d’émigrés russes en Belgique, 1881-1899, Conferentie Benerus: België, Nederland, Rusland: betrekkingen en beeldvorming, Rotterdam 7-8 mei 1987: Belgisch-Nederlandse conferentie over de politieke, economische en culturele betrekkingen tussen België c.q. Nederland en Rusland/de USSR met nadruk op de periode na 1917, Erasmus Universiteit Rotterdam, Katholieke Universiteit (Leuven), Rijksuniversiteit Leiden, 1987.

[8] Vladimir BARTOL, Alamut, Libretto collection, Paris, Libella, 2012.

[9] Julius CAESAR, The Gallic Wars, translation by W. A. McDEVITTE and W. S. BOHN, Book 8, http://classics.mit.edu/Caesar/gallic.8.8.html – de BURY, Histoire de la vie de Jules César, suivie d’une dissertation sur la liberté où l’on montre les avantages du Gouvernement monarchique sur le républicain, Paris, Didot, 1758. For example, p. 86 : ‘he impressed upon them the importance of becoming masters of a rich and opulent city, which would give them all things in abundance, and strike terror into the hearts of all the other cities that had left his party, if they triumphed before it was rescued’.

[10] Deutsche Geschichte in Dokumenten und Bildern, Band 1, Von der Reformation bis zum Dreißigjährigen Krieg 1500-1648, Die Apokalypse vor Ort – Die Zerstörung Magdeburgs (1631) – A Local Apocalypse, The Sack of Magdeburg (1631), German Historical Institute, Washington DC, http://germanhistorydocs.ghi-dc.org/sub_document.cfm?document_id=4396

[11] The severity of punishments is fitter for despotic governments, whose principle is terror, than for a monarchy or a republic, whose spring is honour and virtue.’ MONTESQUIEU, The Spirit of the Laws, Book 6, Chapter 9, Geneva, 1748.

[12] (…) government being for the preservation of every man’s right and property, by preserving him from the violence or injury of others, is for the good of the governed: for the magistrate’s sword being for a “terror to evil doers,” and by that terror to enforce men to observe the positive laws of the society, made conformable to the laws of nature, for the public good, i.e., the good of every particular member of that society, as far as by common rules it can be provided for; (…) John LOCKE, Two Treatises of Government, Ch. IX, Of Monarchy by Inheritance from Adam, 92, London, Thomas Tegg & alii, 1823. McMaster University Archive of the History of Economic Thought. http://socserv2.socsci.mcmaster.ca/econ/ugcm/3ll3/locke/government.pdf

[13] Alain REY, Dictionnaire historique de la langue française, vol.3, p. 3803, Paris, Robert, 2006.

[14] Ariel MERARI, Du terrorisme comme stratégie d’insurrection, in Gérard CHALIAND and Arnaud BLIN ed., Histoire du terrorisme, De l’Antiquité à Daech, p. 31, Paris, Fayard, 2015.

[15] Thomas HIPPLER, Le gouvernement du ciel, Histoire globale des bombardements aériens, p. 156-160, Paris, Les prairies ordinaires, 2014.

[16] Denis PESCHANSKI, Claire MOURADIAN, Astrig ATAMIAN, Manouchian: Missak et Mélinée Manouchian, deux orphelins du génocide des Arméniens engagés dans la Résistance française, Paris, Textuel, 2023.

[17] See Ugur GURBUZ ed, Future Trends and New Approaches in Defeating the Terrorism Threat, Amsterdam-Berlin-Tokyo-Washington DC, IOS Press, 2013, especially Ozden CELIK, Terrorism Overview, p. 1-17 and Zeynep SUTALAND & Ugur GÜNGÖR, Future Trends in Terrorism, p. 75-87

[18] Ariel MERARI, op.cit., p. 42.

[19] Maurice LACHÂTRE, Dictionnaire français illustré, vol. 2, p. 1413, Paris, Librairie du Progrès, 1890.

[20] Anne-Marie LE GLOANNEC, Bastien IRONDELLE, David CADIER, New and evolving trends in international security, Transworld, FP7 Working Paper, 13, April 2013, p. 14.

[21] Raymond ARON, Paix et guerre entre les Nations, p. 176, Paris, Calmann-Levy, 1962.

[22] United Nations, Resolution adopted by the General Assembly, Measures to eliminate International Terrorism, A/RES/54/110 https://www.treasury.gov/resource-center/sanctions/Terrorism-Proliferation-Narcotics/Documents/A-RES-54-110.pdf

[23] NATO Glossary of Terms and Definitions (English and French), NATO (NSO), 2021.

[24] Council Framework Decision of 13 June 2002 on combating terrorism (2002/475/JHA), Official Journal L 164 , 22/06/2002 P. 0003 – 0007.

[25] Jenny RAFLIK, Terrorisme et mondialisation, approches historiques, p. 24, Paris, Gallimard, 2016. – It could also be interesting to open a discussion in order to compare this with Abu Mus’ab al Suri’s definition and typology of terrorism. See Key excerpts of The Global Islamic Resistance Call in Brynjar LIA, Architect of Global Jihad, The Life of al-Qaida Strategist Abu Mus’ab al-Suri, p. 382-383, London, Hurst & Company, 2014.

[26] J. RAFLIK, op. cit., p. 41.

2 commentaires

Laisser un commentaire

%d blogueurs aiment cette page :