This relatively clear conceptualization of combat, however, suffers from a number of glaring limitations. The nature, form and size of the battle have indeed varied considerably over the centuries and especially since the beginning of the industrial era.

A French historian, General Jean Colin¹⁵who was killed by the enemy in Macedonia in 1917, had envisioned as early as 1911 the fundamental turning point that would occur during the First World War. According to him, the battles would extend across time and space. They would be characterized by methods of siege warfare, in which long-range artillery would predominate. It would be difficult to exploit breakthroughs, and finally, material power would outweigh the moral strength and qualities of the fighter. It had indeed been foreseen as early as the Civil War that warfare practice would be profoundly altered through essential mutations. Firstly, the advent of large-scale movement warfare, which characterized most revolutionary and Napoleonic campaigns, already foreshadowed profound changes in the way in which weapons (infantry, cavalry, artillery at the time) were engaged and then used in battle. The "modern" divisional system imagined by Lieutenant-General de Bourcet¹⁶The new system, actually implemented and then optimized by the Emperor with the creation of the corps level, effectively allowed for a profound evolution in the art of conducting operations. The nature of the battle was thus transformed in the space of a century, less because of the evolution of armaments than because of the responses to the logistical difficulties of the time, the progress of the means of communication and the increase in manpower from the First World War onwards.

The second major change was the transition from the shock effect to the supremacy of fire, which was definitively established with the hecatomb of the summer of 1914. From this turning point onwards, as Western armies became more and more technologically advanced, the ability to hit the adversary in a manner that was more and more effective was becoming more and more important.From this point onwards, as Western armies became more and more technologically advanced, the ability to reach the opponent in an industrial manner and without direct contact profoundly changed the nature of combat, gradually wrenching it away from the systematic logic of melee and hand-to-hand combat. Thus, the battle was characterized since the Neolithic, until the battles of Tannenberg and La Marne in 1914, by a generally brief and violent engagement of a few hours, culminating with an assault phase intended to break the coherence of the opposing device. From the First World War onwards, another form of battle was substituted, consisting of a succession of battles in a single engagement lasting several weeks or even months (Verdun, Stalingrad, Kursk, Mosul). With very few exceptions (Dien Bien Phu for example), no really decisive battle could be observed in the second part of the twentieth century. From this observation, a trainee of the École Supérieure de Guerre, Major Guy Brossollet, in the mid-1970s, wrote a daring thesis for the period¹⁷in which he questions the necessity of the battle against a numerically superior opponent. It proposes a modular and in-depth defence system that will later inspire German thinking on techno-guerilla warfare, successfully implemented by Hezbollah against Israel in 2006.

But the fundamental fact that has really transformed the nature of the battle is the now permanent porosity between the civil and military spheres in warfare. The war having become total, the battle implies a complete mobilization of all the resources available to fight. The final annihilation or complete exhaustion of the resources of one of the belligerents is therefore now the only limit to the battle, except when one of the adversaries considers that the cost of victory has become exorbitant. This was the case with the Second World War, where no truly decisive battle could really be observed. The British historian Hew Strachan makes the same observation. "Because the battle is between a winner and a loser, it would represent an end in itself. But with the ability for nations to re-equip their armies comes the prospect of battles without limits in time and space. The era of the decisive battle seems well and truly over".¹⁸. This rediscovery of unlimited warfare among peoples, systematised from decolonisation conflicts, makes a global approach to operations, both civil and military, essential. Military victory alone remains indispensable but insufficient to guarantee lasting peace.

" Men should know when they are defeated. Would you know this, Quintus?Would I know? »

To conclude this brief statement, nothing in a battle between Roman legions and Germanic tribes would probably have resembled the scene imagined and filmed by Ridley Scott. However, the author of these lines recommends viewing the film, because the general quality of the film and the quality of the acting more than makes up for the obvious lack of historical realism for the undemanding seventh art lover. Beyond the cinematographic and tactical reflections inspired by this scene, this work finds another interest. It testifies to a certain fasci nationhood of our contemporaries, particularly among our American allies, for the technological fact. The very Manichean representation of af frontement also questions the capacity that Westerners generally have to understand otherness, adversity in all its forms and the complexity characterizing the battle environment. Today's strategic and tactical thinking is naturally deeply attracted to and marked by the promise of new technologies. However, this approach has historically proven to be generally ineffective. As the British historian Lawrence Freedman rightly points out, the "constant temptation to believe that there are technological solutions to essentially political problems" is a "constant temptation to believe that there are technological solutions to essentially political problems".¹⁹ does not prompt either futurists or strategists to take into account foreseeable operational disruptions in a sufficiently comprehensive manner. The main problem lies in the difficulty of accurately determining the likely impact of a new technique on the art of warfare. Often this impact is either underestimated or overestimated, or it produces effects quite different from those expected. History also shows, and our recent engagements prove it, that technology and firepower do not guarantee victory or peace if the use of this superiority is not guided by ambitions and political will clearly established even before engagement in combat. The absence of a definition of political-military and strategic objectives is in itself a guarantee of failure. The resurgence of the pre-eminence of the moral factor, understood collectively, over the technological fact, thus gives a completely different resonance to this famous quotation from Marshal Foch: "To accept the idea of defeat is to be already defeated".