The Myth of Military Logic

How "military necessity" became the key-stone of militarism

Is there such a thing as the logic of war? Appeals of countless officers throughout history to “military necessity” suggest that there is. Yet, Clausewitz tells us there is not. According to him, “war has a grammar of its own, but not its own logic.” What does this mean and why have officers proven willing to nevertheless appeal to a “military logic” in their conflicts with civilian authority? 

“War is too serious a matter to entrust to military men.”

-Georges Clemenceau, French PM, 1906-09, 1917-20

The idea of “military logic” is a product of the professionalization of war. When the practice of war is more than an occasional duty it becomes both useful and socially necessary to delineate a sphere of knowledge that belongs to the profession. Arguments for or against different courses of action are not merely differences of opinion, but involve the assertion of special knowledge; the expertise that privileges the view of a professional. Yet, war is a matter of vital importance to the state and virtually all statesmen have found, like Clemenceau, that it is “too serious a matter to entrust to military men.” War is inextricably political and therefore the attempt to delineate a “purely military” realm of expertise has created civil-military conflict. 

Why then, is there not a military logic? Certainly, soldiering as a profession involves a collection of skills that are not found in other contexts. How to siege a fort or drill a battalion is knowledge of its own kind. This kind of technical expertise certainly has a logic: that of combat efficacy. Yet this goal must be forever subordinated to political interest whenever the two conflict. For instance, mass bombardment may be avoided during a siege for diplomatic or humanitarian reasons even if they would compel a quicker surrender. Thus, political logic subordinates military efficacy. Victory is only one of many means available through which policy goals may be achieved and policymakers have the right to run risks or bear costs in terms of military efficacy. 

All military action is contextualized by the political circumstances in which it takes place. Pursuing and destroying a defeated army may be an enormous advantage if the overthrow of your opponent is desired, but it may be a disaster if you are intending to align with them against a third party in the future. The Austrians in the war of the Sixth Coalition sought to avoid totally defeating the French for this precise reason. Thus, we must ultimately concur with Clausewitz when he says that war has no logic of its own, but rather borrows its logic from policy. War introduces the elements of passion and chance to this logic, but the logic remains of the political kind, merely applied to unpeaceful circumstances. 

It is from this principle that the rather radical, but entirely correct, assertion of Clausewitz that professional military expertise must in all cases give way to political priorities. Military professionals are placed in the perhaps unique situation of practicing their profession exclusively while subject to the interference of non-experts. As in no other field, professional authority is eternally contingent. At any time, political authority reserves the right to interfere, down to the most minute level. Because war is ultimately for political purposes, it is the political leadership that is competent to weigh military and political priorities. It cannot be left to professional soldiers (Clemenceau’s “military men”) to decide if forgoing military advantage for political purposes is justified. The policymakers must decide whether running great risks to attain a great victory is necessary or whether the state may be equally well-served by a more modest aim. The professional soldier can only seek to communicate the military merits of each course of action. The lot of the officer is thus frequently the frustrating position of having to attempt to distill expert assessments into a form that is not just comprehensible but persuasive to non-experts. Beyond this, they must resign themselves to the fact that reasoning from a field outside their own may entirely nullify their professional assessment of the situation. 

“Never have I admired and despised a man simultaneously to the same extent.”

-Field Marshal Alan Brooke, on Winston Churchill

A signal example of this problem is found in the war diaries of Viscount Alanbrooke, chief of the Imperial General Staff during the Second World War. Throughout the document, what most comes across is the impression that his primary contribution to British victory was preventing Churchill from initiating any number of impractical schemes that would have almost certainly resulted in disaster. Because Britain had embraced the principle of civilian supremacy (in line with Clausewitz’s judgment) Alanbrooke had no authority to veto these plans. Anyone familiar with Churchill's implacable and combative reputation can imagine the difficulties involved in convincing him to abandon ideas that caught his fancy. Alanbrooke is deservedly lauded as a great general in no small part due to his ability to persuade civilian leadership. Churchill likewise is remembered as a great wartime leader in no small part due to his willingness to be persuaded.¹ An unconvincing officer or obstinate political leadership would have produced disastrous results. 

“It is always right to probe.”

-Winston Churchill

Officers operating at the highest levels must therefore possess sufficient political insight to know when military opportunity is being deliberately sacrificed for political benefit as opposed to as a pure blunder. This skill of professional empathy is no less important for introspective reasons. The close interrelation between policy and military affairs particularly at the highest levels mean that it requires active effort to avoid judgments of policy masquerading as military assessments. 

Moltke at Königgrätz

Never has an officer failed to find a military objection to a policy decision they disagreed with. This was the original sin of the Prussian army under the Elder Moltke. In an effort to clearly define the authority of the General Staff he purported the existence of iron-clad military logic over which civilian interference could produce only harm. War, in his view, was a technical exercise. While directed at a political object, the route there could only be charted by professionals with the expertise to do so. This was very much the product of the army’s chafing under the constraints of Bismarck, a statesman who very much understood the dangers of excessive military success. 

 The idea that a campaign could be planned under “military logic” did untold damage to the strategic culture of the German army. Without political direction, the army axiomatically aimed at the total defeat of the enemy, even when such a victory was not only unnecessary, but actively counter to national interest. This concept infected civilian leadership and even the monarchy itself such that military views were privileged over political assessments. The concept of “military necessity” was given the place that rightly belonged to “political expediency.” It was forgotten that what risks and costs could be borne militarily had to be determined politically. Inverting the formula left this assessment undone, leaving nothing more than a strategy of default. 

It was this absence of conscious strategy that brought Germany to war in 1914. The Kaiser, his ministers, and the military cabinet could readily answer that they hoped victory in a European war would bring Germany its “place in the sun.” But there was no clear understanding of what that meant in terms of policy concessions it desired from the Entente. It is emblematic of this that the war aims of the German Empire (the “Septemberprogramm”) was developed only after the outbreak of a war that was long desired. War was not thought of as a means to achieve specific objectives, but “victory” was turned into a talisman, a mere technical concept that required no further processing to convert into whatever was desired. 

This magical thinking was the product of the missing link between military means and political ends; in a word, strategy. This is at the core of Clausewitz for, without the primacy of policy, strategy is impossible. The example of the long-suffering Alanbrooke is illustrative of the thankless job of military expertise. Final authority forever rests in the hands of non-experts and the effectiveness of senior leadership is contingent on the ability to establish a positive working relationship. However tempting it may be to dispense with such coordination and seek a clear delineation, the German case should serve as a warning against it. Strategic action is only possible when the inextricable relationship between means and ends is acknowledged. 

The challenge for military professionals is therefore to avoid the trap of the hubris of Schlieffen and the German general staff, of asserting the supremacy of their expertise and “military necessity” over policy decisions. Alanbrooke was fortunate in that Churchill, for all his argumentative nature, was willing to be persuaded. Civilian leadership is under no obligation to yield to even the most fervent appeals of military experts. Military professionals must chart a course between the Scylla of being ignored and Charybdis of depriving policy of its necessary place of primacy. 

1. https://foreignpolicy.com/2017/08/30/churchill-had-his-faults-but-he-was-a-far-better-strategist-than-his-generals-were-2/