The study of the enemy has no other purpose than action. Every military leader, especially within NATO[1], needs the same information to be able to design his own maneuver: studying his enemy should therefore be done identically in all member countries. In fact, most analytical approaches used in the armed forces are already based on identical principles (such as adaptation to the mission and environment). Moreover, whatever the method used, the modelling of the enemy is generally divided into two major successive and complementary steps: firstly, the description of the enemy (who he is, what he wants), and secondly, his modes of action (how he can obtain it). Everything thus seems to encourage methodological uniformity within the Alliance. However, when it comes to conceiving the hypotheses of enemy manoeuvres, the approaches diverge: NATO [2] differentiates between the "most dangerous" and the "most probable" mode of action, formulations that are non-existent in the French method. Is this difference merely formal or does it hide a certain heterogeneity of thought?

1] In the initial study that led to this article, the American, British, NATO and French methods were compared.

[2]. Comprehensive Operations Planning Directive (COPD), Allied Command for Operations, 2010.

A point-by-point comparison of each method could be as tedious as it is unproductive. It is therefore necessary to look at the spirit behind the method, the approaches, the "ways of approaching a subject" [1]. 1] Intimately linked to the military culture of each nation, they reveal different intellectual postures, especially between France and the rest of NATO. The alliance has opted for a probabilistic approach that permeates much of its methodology [2]. 2] France, for its part, retains a more "possibilistic" vision, which it reaffirmed in 2014, both in its intelligence doctrine and in its reference documents for operational design. 3] Rather than opposing them, cultivating this diversity could prove very useful, given the interesting complementarity of these concepts.

Probabilism or possibilism, an old story.

The origin of this difference may be to be found in the very way military intelligence is approached. As early as the 1930s, Colonel Bernis, a French strategist and author of an Essay on Intelligence in War, evoked two schools of thought that have been opposed since the 19th century[4]. 4] The so-called "school of possibilities" is associated with Napoleon, who was wary of intelligence that he always considered to be quick to confirm the first impression. This approach recommends "never trying to imagine what the adversary will do,"[5] but rather to focus on what is within his reach, given his means and his situation. This means considering all the assumptions, technical and tactical possibilities and directing intelligence accordingly. Conversely, the "school of intentions," which Bernis associates with the Prussian marshal Helmut von Moltke, consists of "starting from a situation [...] which is the basis for the intelligence of the enemy....] doctrine and procedures ... to determine the adversary's intention and the manoeuvre he will execute. [6] The idea is to concentrate the means on a few hypotheses, the most probable ones only, in order to "reduce the field of possibilities". Each school has its advantages and weaknesses. The first is more open but disperses its resources, the second rationalizes its means but focuses reflection in a very intuitive, even arbitrary direction. The parallel with the two current ways of apprehending enemy modes of action is so obvious that it is difficult not to see a filiation between them.

NATO's probabilism: in the beginning was intelligence.

NATO's approach to intelligence is clearly "probabilistic", perhaps linked to Moltke's vision, but in part correcting excesses. This process consists of devising a wide range of modes of enemy action and classifying them according to two criteria: probability and dangerousness. Only the most dangerous and the most probable mode of action are selected to be later confronted with the various friendly options and thus determine the most desirable maneuver. In a somewhat dogmatic way, this process excludes by construction that the most probable of the options may also be the most dangerous. This can be explained by this very Anglo-Saxon vision, for whom surprise is considered to be the major risk: the predictability of an action reduces its danger all the more. It is thus possible to model this approach according to an enemy modes of action (EMO) curve, a function of probability and dangerousness (graph 1). This then resembles a branch of decreasing hyperbole: options that are both improbable and harmless are naturally eluded.

In fact, the intellectual effort is therefore focused on researching and developing the most probable option. In practice, the most dangerous mode of action is often quite caricatural, taking the form of an enemy throwing himself with all his means and brutality into a quasi-suicidal but destructive operation. By starting from a selection of numerous hypotheses (the method recommends at least three) and trying to classify them according to precise criteria, this approach avoids the pitfall of Moltke, who concentrated on a single option, the one he considered most likely. This model keeps this in mind, trying to guess what the adversary will most logically do to bring the intelligence effort, which this model massively needs. Finally, the risk of mental "tunnelling" of the school of intentions is weighed by determining the most dangerous hypothesis. The latter serves above all to guard against an operational surprise: "even if the worst happens, we have anticipated it and our manoeuvre remains tenable [7]".

French possibilism or the culture of uncertainty.

French doctrine opts for a so-called "possibilities" approach. Like the previous one, it has also been adapted to avoid its pitfalls. In this approach, there is no evaluation or distinction between probability and dangerousness: two and only two modes of action are determined which must be both probable and dangerous. They are defined by trying to put oneself in the enemy's place, to manoeuvre like the enemy based on the elements determined by the preliminary study (capabilities, doctrine, objectives, etc.) and considering the particular environment. If it had to be represented graphically, the modes of action curve would be very different from the NATO approach (Graph 2). The range of hypotheses is deliberately reduced: the most probable non-dangerous or the very dangerous non-dangerous ones are not studied for pragmatic reasons. In the first case, a simple driving measure will make it possible to deal with the situation, so it is better to concentrate on the most dangerous hypotheses. In the other case, the improbability of the scenario leads the staff to reserve its resources for more realistic cases. The difficulty of the exercise is that these two modes of action studied must also be sufficiently differentiated [8] to allow for a real choice in the friendly manoeuvre.

By limiting the field of investigation to two credible hypotheses, this model seeks to compensate for the drawbacks of the initial school by inserting a dose of intention. Above all, it keeps in mind that the enemy is perceived as unpredictable by nature. The modes of action retained by the study are considered probable, but fundamentally uncertain[9] : they are therefore described in a fairly general, imprecise manner and correspond almost to two "families" of possible modes of action rather than to two actual detailed manoeuvre hypotheses.

The translation of different but complementary mental postures.

Thus, these two analytical models are not only methodological: they reveal a fundamental difference in the way of "thinking" the enemy's manoeuvre. The singularity of the French side is to adopt a pragmatic approach, saving means and leaving more room for uncertainty. It also reveals a more humble stance in the face of the enemy, considered capable of combining originality and dangerousness.

These two different intellectual postures have far-reaching consequences on the conception of the enemy, as well as on the orientation of intelligence research. A probabilistic approach requires significant resources and quality. A sufficient 'statistical sample' of modes of action must be developed (which requires personnel) and then classified according to probability. and hazardousness (which raises the question of evaluation criteria, the availability of specific intelligence and analytical tools, and the arguments for such a ranking). Finally, for the "most dangerous" mode of action to have some relevance, the force must be robust enough to deal with it in spite of everything, without fundamentally undermining its mission or integrity. This method is therefore more appropriate for strategic and operational headquarters with large capabilities or forces capable of dealing with the "worst" if it comes to it. The French approach, perhaps influenced by a chronic lack of means and some reservations about the expectations that can be placed on intelligence, cultivates the idea that it is impossible to know what the enemy is going to do. It deliberately limited its investigations to two very different but credible options on which to build a maneuver that was by nature imperfect. It therefore initially requires fewer means of research and analysis [10]. 10] In fact, it is well adapted to operational and tactical staffs, with more limited capabilities.

The French approach has the weakness of ignoring heterodox hypotheses, which potentially exposes it to a tactical or even operational surprise. Thus, an enemy mode of action consisting of throwing all its forces in an ill-considered manner, on the main line of defence and by the most probable axis of approach will surely be excluded from the study, as it is considered too irrational. However, this type of manoeuvre can potentially succeed because of the surprise effect it can generate. The French approach, however, intellectually accepts greater uncertainty as to the enemy's intentions. By creating a culture of action in the unknown, it obliges and accustoms the staff to a certain reactivity in the face of an unexpected situation. In the NATO culture, by contrast, the main risk is the creation of a "tunnel effect": the cognitive resources of analysts may be focused on the most probable hypothesis, insofar as it is the only credible one, and consider the most dangerous one as a mere exercise in form. Since its reaction capacity is less able to react in the event of an unforeseen enemy mode of action, the staff must compensate with superior knowledge of the adversary. Indeed, the probabilistic approach makes the staff structurally more dependent on intelligence from the outset of planning.

In conclusion, a fundamental difference is evident in the way of anticipating adversary modes of action, depending on whether one uses the French possibilistic approach or NATO's more probabilistic approach. These two dissimilar approaches within the same alliance are not only questions of form or methodology: they reveal a rather different intellectual posture and relationship to the enemy. The "by the possible" approach remains deeply rooted in the French military culture, especially at the tactical level, while the probabilistic method has become the norm within the rest of NATO [11], especially from the operational level.

The normative interest that the Alliance brings to multinational operations is indisputable, as is the need for France to develop its interoperability with its allies through the adoption of common procedures. Nevertheless, it would seem very useful to maintain the "what can be done" approach. Faced with the generalisation of NATO's probabilistic approach, the French school should resist it, in particular through the intellectual agility that it instils in operational staffs. By cultivating its specificity, France would help to diversify thinking about the enemy, a guarantee of effectiveness in a field where, more than elsewhere, the certainty of always being right often leads to failure.

1] According to the Larousse dictionary.

2] Whether in its analyses of risks and threats, as in this particular case of the definition of modes of action, or in its analysis of the risks and threats.

[3]. CDT 60.001, Méthodologie d'élaboration d'une décision opérationnelle tactique, CDEF, Armée de Terre, Ministère de la Défense, Paris, 2014.

[4]. H. Coutau-Bégarie, "Le renseignement dans la pensée militaire française", Stratégique, n° 73, 1991, available at : www.institut-strategie.fr.

[5]. 5] Ibid., p. 30.

[6]. Ibid, p. 30., p. 31.

[7]. Interview with an American officer in training at the School of War, October 2017.

[8]. Enemy modes of action must be both general enough to be inclusive and differentiated enough to be well-characterized and dissociated. Only under these conditions can the leader have a clear choice in the maneuver to adopt.

[9]. 9] In this regard, it is interesting to note that in France, the use of the conditional is mandatory when it comes to describing the enemy in operational documents.

[10]. These means are rather reserved for the conduct phase (not mentioned here) where it will be necessary, during the action, to confirm or inform the maneuver hypotheses before restarting the process for the next action.

[11]. 11] This approach was enshrined in the adoption of the Comprehensive Operations Planning Process (COPD) in 2010 as NATO's official method for operational planning. It is used by most of the French staffs with operational capability (in particular CRR-FR in Lille and CPOIA in Balard).