What Is Irregular Warfare?

Irregular warfare is a fundamentally European concept that arose in the 18th century to refer to the reverse of a set of practices and representations established as norms for armed conflict. Whether consciously or not, irregular combatants defy modern western military categories, in tactical and strategic terms, as well as in political and legal ones. In its various forms, irregular warfare has resulted not only in guerrilla warfare campaigns against occupying armies but also in clandestine or subversive actions aimed at surprising or circumventing a more powerful foe by attacking it logistically or politically behind the lines. With the reduction in the classical battle model immediately after World War II, irregular warfare has gradually imposed itself as the dominant mode of conflictuality, through both guerrilla warfare and terrorism. This prevalence is the result both of indirect confrontations between major powers and of asymmetrical conflicts following decolonization.

“Guerrillas in the Peninsular War” by Roque Gameiro in Images de l’histoire du Portugal, 1917.
“Guerrillas in the Peninsular War” by Roque Gameiro in Images de l’histoire du Portugal, 1917. Source : Wikimedia Commons
Arab fighters in Aqaba on February 28, 1918. Autochrome color photograph
Arab fighters in Aqaba on February 28, 1918. Autochrome color photograph. Source : Wikipédia
ELAS guerrilleros during the Greek Civil War.
ELAS guerrilleros during the Greek Civil War. Source : Wikimedia Commons
Terrorism, a kind of irregular warfare, New York, September 11, 2001.
Terrorism, a kind of irregular warfare, New York, September 11, 2001. Source : Wikipédia

It has been amply demonstrated that, far from being a form of absolute violence, war is a socially constructed activity reflecting both the values and the political and economic organization of the societies involved. The European conception of conflictuality is no exception to that rule: it meets the standards corresponding to representations that have been forged over the course of its history. It juxtaposes different heritages: Greco-Roman and Judeo-Christian founding myths, Medieval traditions for regulating violence (e.g. the “Peace of God”), evolutions tied to the emergence of political modernity from the 15th to the 18th  centuries (state apparatuses, standing armies), social, legal and economic evolutions from the 19th and 20th centuries (nationalism, industrialization, rise of international humanitarian law). These have led to a kind of “ideal type” of armed violence that is sometimes known as “regular” or “conventional” warfare, and which dominates our representation of war. In opposition to that model, a form of conflictuality that is described – in a normative and ethnocentric manner – as “irregular” has emerged. The term refers to military practices that don’t comply with the representation of warfare that dominates in the western world.

The Reverse of European Military Modernity

The concept of irregular warfare was composed negatively, relegating any armed violence that did not conform to the western canon to a kind of “perfidy” – when it took place between enemies with the same political frame of reference – or “barbarianism” – particularly during colonial wars against non-European adversaries.

In political and legal terms, irregular combatants do not recognize the principle of a state defined exclusively, according to Max Weber, by its monopoly on the legitimate use of force. Whether they are revolutionary or reactionary, independentist or separatist, irregular combatants’ actions, in and of themselves, contest the legitimacy of the established regime. So they situate themselves outside of positive law, which often leads to them being described as bandits or criminals. If they refer to transnational political or religious solidarity, as they sometimes do, they expose themselves to the accusation of being foreign agents. Lastly, irregulars tend to reject the distinction between combatants and non-combatants. That fundamental norm in human rights – present as far back as the Middle Ages in Thomas Aquinas’s writings, then more centrally in the philosophy of Hugo Grotius, the father of modern international law – took on a particular materiality during the Renaissance, with military uniforms, for instance. So the absence of uniforms is one of irregular combatants’ defining characteristics: by mingling with the civilian population, they expose that population to their adversary’s indiscriminate repression.

Norms apply on a tactical level as well. While conventional armies have focused their efforts on a continuous increase in fire power, irregular forces count on mobility, “The sudden change of surprise attack and retreat” as the German jurist and philosopher Carl Schmitt put it in his Theory of the Partisan (1963). Facing ever more industrialized and technology-focused armies, irregular fighters focus on compensatory tactics: ambushes, surprise attacks, concealment and evanescence.

In contrast to the classical tradition, based on the destruction of the enemy army, irregular strategy is more indirect, endeavoring to erode the other side’s determination. “The guerrilla wins if he does not lose,” Henry Kissinger wrote in 1969, referring to America’s experience in Vietnam. In order to survive while wearing their opponent down, irregulars aim for small victories through harassment, sabotage and sapping power relays in the territories where they become established. In so doing, they resort to kinds of economic or social mobilization to build — by whatever means necessary — popular support, which grants them political legitimacy, as well as human and material resources. 

Irregular Warfare through the Ages

Irregular warfare has undoubtedly always existed, motivated by the difference in weapons and manpower between two sides: Julius Caesar’s Commentaries on the Gallic War is bursting with accounts of asymmetrical confrontations with Roman legions. While the methods continued into the modern era, the establishment of standing armies in the 17th century and the growth in their size and logistical needs explains the development of harassment tactics aimed at supply lines. The 18th century saw a professionalization of these “skirmishes” or “small wars.” They are also known in French as “party warfare,” because small detachments, or parties, lead attacks against the backlines. That is where the term “partisan” comes from. 

With the emergence of national sentiments in the 19th century, skirmishes became more generalized and more and more often took the shape of popular resistance to a foreign enemy. That was the case during the Napoleonic Wars with the Spanish guerrilla, the 1812 Russian partisans, and even the 1813 Prussian Landwehr. While the second half of the 19th century saw other episodes of this type in Europe, such as France’s francs-tireurs in 1870, the practice of small warfare disappeared in favor of confrontations between larger regimented masses. Outside of Europe, however, colonial conquests led to a multiplication of asymmetrical conflicts that gave rise to new pacification doctrines coming from France and the United Kingdom, as well as Russia and the United States.

The advent of total war at the turn of the 20th century launched a new transformation of irregular warfare. During World War I, the strategic importance of the “home front” (mobilization of the civilian population for the war effort) increased the fear of subversion from the inside. Dropping defeatist leaflets and spreading “fake news” introduced the idea of propaganda as a weapon of war. Guerrilla warfare was part of that: here and there, it was a way of getting around a battlefield paralyzed by siege warfare. German support for the 1916 Irish insurrection and British support for the 1917 Great Arab Revolt are two examples of that. World War II accelerated that logic, notably due to the influence of Great Britain, which established an organization for “political warfare” and “special operations” aimed at bolstering resistance in territories occupied by the Axis powers.

After 1945, Cold War logic reinforced the indirect strategy, and, therefore, irregular warfare. Propaganda, subversion, clandestine actions in support of armed groups became necessary tools. In Europe, that could be seen in both the Greek Civil War and the Anglo-American secret services’ attempts to destabilize Albania. But that form of conflictuality was established most durably in what was then referred to as the “third world”:  as an asymmetrical strategy, irregular warfare soon became the weapon of choice in the wars of national liberation that brought the European imperial order to an end from 1945 to 1975.

In many nations in Africa and Asia, the colonial era led into civil wars, separatist rebellions and other forms of armed struggle, which has extended irregular conflictuality into the present. Finally, terrorism emerged in the early 1970s as a new weapon in irregular warfare. First employed by revolutionary movements (the Red Brigades in Italy, and the Red Army Faction in Germany) and nationalist ones (Palestinian, Irish, Basque), it was adopted in the early 1980s by a new cause: Islamic jihadism. Since the September 11, 2001 attacks, that movement has gradually taken a central position in irregular conflictuality.

Translated by Regan Kramer

To quote from this article

Elie Tenenbaum , « What Is Irregular Warfare? », Encyclopédie d'histoire numérique de l'Europe [online], ISSN 2677-6588, published on 30/11/23 , consulted on 03/03/2024. Permalink : https://ehne.fr/en/node/21670


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