Aerial Bombing

Giulo Douhet 1869-1930
Giulo Douhet 1869-1930

Rotterdam being bombed, 1940
Rotterdam being bombed, 1940
In this article Moseley reviews the emergence of aerial bombing in the early twentieth century and its relationship to legal codes and the just war conventions

With the advent of planes, it was not long before they were being used by pilots for military purposes - initially for reconnaissance and then for shooting at each other in the sky. But as the First World War proceeded, some pilots were dropping small hand-held bombs from the sky on the enemy below and by the 1920s the potential of this kind of warfare was grasped by writers such as Douhet. The ethical repercussions quickly followed too - was aerial bombing a form of terrorism that should be prohibited, unless it could be guaranteed to hit legitimate targets precisely? Is it just an extension of the artillery arm, similar to artillery fire for instance, and therefore no new ethical issues arise? Are there situations in which aerial bombing should categorically not be employed?

In Command of the Air, Douhet envisaged how an air force could revolutionize warfare by targeting the enemy's industry, the infrastructure, the government, and importantly, the 'will of the people'. Bombing from great heights would frighten an enemy into submission, he reasoned - his theories were taken up and developed in the Second World War by advocates such as Sir Arthur Harris, who said to the RAF in 1942: "We are going to scourge the Third Reich from end to end. We are bombing Germany city by city and ever more terribly in order to make it impossible for her to go in with the war. That is our object, and we shall pursue it relentlessly."

Unsurprisingly, Douhet and his fellow thinkers, were supporters of total war in which the enemy's civilians were seen to be as justifiable targets as were its combatants. No distinction was thus to be drawn between combatant and non-combatant, and thereby one of the most important pillars of just war theory was to be rejected - the principle that combatants ought to discriminate between targets. Nonetheless, aerial bombing does not necessarily imply total war: if enemy combatants and the appropriate military infrastructure are targeted then the issue falls back into the principles of just war theory.

Aerial Bombing and Legality

Legally, aerial bombing was considered to be an extension of artillery fire and was assumed under the Hague Conventions of 1907:

Article 25: The attack or bombardment of towns, villages, habitations or buildings which are not defended, is prohibited.
Article 26: The Commander of an attacking force, before commencing a bombardment, except in the case of an assault, should do all he can to warn the authorities.
Article 27: In sieges and bombardments all necessary steps should be taken to spare as far as possible edifices devoted to religion, art, science, and charity, hospitals, and places where the sick and wounded are collected, provided they are not used at the same time for military purposes.
The besieged should indicate these buildings or places by some particular and visible signs, which should previously be notified to the assailants.

An amendment to the Conventions was proposed in the "inter-war years" (1918-1939) stipulating that: "Bombardment from the air is legitimate only when directed at a military objective, the destruction or injury of which would constitute a distinct military disadvantage to the belligerent." Interestingly, the amendment was not ratified, for by then the ideology of totalitarian war (warfare that knew no boundaries) was taking hold of military thinkers, and in the second clause we can read a hint that a defending nation could resort to indiscriminate aerial bombing should a belligerent be militarily disadvantaged - for instance, if a small nation were threatened by overwhelming force, an implication that throws up a host of other moral issues. The League of Nations sought to condemn aerial bombardments of civilian centres and a new Convention was drafted in the Hague in 1938 but which was confined to non-ratification as hostilities once more broke out across Europe. Nonetheless, the draft rules have been considered by many legal theorists to uphold the spirit of the law and a valid extension of the normal laws of armed conflicts - but that they have never been ratified provides a convenient loophole for those who emphasise the need for ratified law (legal positivists): supporters may prefer to underline how they are part of the customary laws of war, a contention drawn from Protocol I, in 1977, which stated that the rules relating to the general protection of the civilian population "apply to land, air or sea warfare which may affect the civilian population, individual civilians or civilian objects on land. They further apply to all attacks from the sea or from the air against objectives on land but do not otherwise affect the rules of international law applicable in armed conflict at sea or in the air." (Quoted in Green, 1993)

The problem that ethicists have with Conventions and legislation is that the laws are often ignored, that their imposition are not backed by the same apparatus that may give substance to domestic law enforcement, this is a particular concern for legal positivists, theorists who believe that law, to be law, must be backed up by the coercive apparatus of the state. So in the absence of a world authority, international conventions are rendered useless. In effect, they remain idealistic visions of how things ought to be, but the reality of international life is such that they are not likely to have any impact. Moreover, even if nations sincerely support such conventions that limit aerial bombing (or other aspects of warfare), historically political ideologies are used to rationalize their breach or to re-interpret the conventions to serve martial rather than moral purposes.

This was particularly notable in the Second World War when cities such as Dresden were bombed that had no military value and were acting as confluences of refugees: aerial bombing had, since its inception, became a weapon of terror and so, arguably, left the moral realm. Interestingly, early on the war, Germany bombed Rotterdam which was considered a garrison town and thereby a legitimate target - unfortunately, the city was about to enter into negotiations with the German commander besieging the city but his order that the aerial attack be halted was not delivered in time.

Historically, the use of aerial bombing reflected a decline in martial ethics towards the civilian population as the twentieth century proceeded (indeed, as twentieth century political thinking pursued a general shift from liberal humanism towards collectivism): was aerial bombing any different than the firing of long range artillery onto civilian areas (or areas in which the number of civilians could construe them as only partially militarized)? In the aftermath of the Second World War, the Nuremberg Trials proposed that the earlier Hague Conventions reflected the laws and customs of war universally so, regardless whether nations or peoples had signed up to the documents.

The reflection of customary expectations in war is a critical part of the just war conditions, but unfortunately the Nuremberg and Tokyo Trials did not turn impartial eyes on the Allied powers that also used indiscriminate bombing leading to the obvious critique that what is meant by the laws and customs of war are those that suit the victor nations. Since the Second World War there have been various examples of aerial bombing that have tested the Hague Conventions and the idealism that such weapons be turned only on other belligerents.

To the extent that Conventions and legal rulings express customary practice and expectations, philosophy encourages to look at the moral content of customs

Justifying aerial bombing.

A justification raised by Douhet's philosophy is that the sheer terror of aerial bombing will break the will of the people into submission. There is indeed historical support for such a contention: when two armies are unmatched in technology, then the lesser equipped army has all the reason to be scared or unsure as how to proceed. However, when both armies are similarly matched, the prospect of terror diminishes - both sides can mentally prepare for the weapons and strategies used. Nevertheless, any form of warfare that is built upon the notion of terrorizing the enemy into submission suggests terrorism, which just war theory and other ethical positions tend to reject.

But could such total war strategies be rescued morally speaking? There is the perennially attractive argument that appeals to total war supporters that targeting civilians to 'break their will' will finish the war sooner than otherwise. Fewer casualties may thus be encountered on the one side, or on both sides - and so a utilitarian calculus may be invoked to justify aerial bombing. This can be detected in the Allied decision to wage indiscriminate aerial bombing on German cities in the Second World War, but critics have noted that the effect of the German bombing on British cities was not to weaken the resolve of the people but rather to strengthen it: why would the enemy population not react similarly is an obvious retort.

Famously, the Luftwaffe used screaming Stuka dive bombers to terrorize enemy troops - and it certainly had an effect on French and Belgian population and combatants, who embarked on a westward rout, thereby impairing the French ability to defend their lines in 1940 (Horne, To Lose a Battle). In that respect, the utilitarian argument holds - the Germans achieved military successes (often beyond their own estimates) to very little loss on their side (when compared to the devastating stalemate of the trench warfare of the First World War), and the Americans employed atomic weapons in the aerial bombing of Hiroshima and Nagasaki in 1945 to end the Second World War. However, when German cities were being bombed, we can stand back and look upon the process of mutual bombing with horror: all sides in the war began to bomb indiscriminately (Coventry, Dresden) and the utilitarian begins to assess the situation differently.

Potentially though, as the casualty levels rise, the justification of indiscriminate aerial bombing becomes less palatable - indeed, it is a useful reminder that in war, combatants generally tend to converge onto mutually respected principles of discrimination and proportionality, arguably because the cost of contravening the historically evolved principles of just war and just conduct in war tend to rise. The exception may be in peoples who wish to wage genocide against another people in which total war is deemed morally acceptable to one side - a position challenged by humanists all flavours.

Discriminate aerial bombing belongs very much within the field of justifiable action within war. It differs from other forms of attack only by the fluidity of the space that it inhabits - a plane, as Douhet observed, may manoeuvre in three dimensional strategies rather than the land or sea locked traditional armies. Originally, he thought that such warfare would make land warfare obsolete, but armies quickly devised defences against air attack. Morally, therefore, the existence and deployment of aerial bombing divisions does not create any new problems that artillery involves. There are differences in the mobility of the air wing as well and the speed of deployment, but these are matters of gradation rather than presenting a revolutionizing ethical issue within military ethics: both aerial bombing and artillery involve a geographical distance that in effect creates a moral distance between the combatants - an ethical problem that was really invoked in the shift towards long range weapons such as bows and arrows, never mind cannons and cruise missiles.

Between the two positions of discriminate and indiscriminate bombing are the problems of incidental casualties that are common to forms of aerial bombing, even in the present era of supposed 'precision' bombing and laser-guided bombs. The devastation and incidental deaths caused by such policies is well-documented, which leaves the possibility that the terminology is employed as a moral cover for what is inherently a potentially indiscriminate weapon. The sceptic may ask why use the cover at all - and reply that it could be for political reasons to secure support for bombing enemy targets in the domestic polity. Perhaps the appeal lies more with the idealism of the technology - that targets could be discriminated between holds hope that a morality of war is no veneer to support naked aggression, but is in effect a sincere attempt to reduce or to eliminate collateral casualties in wars, particularly those that affect civilian populations.

However, the factor of moral distancing remains: a pilot guiding a plane to drop bombs upon enemy targets (legitimate or not) is morally separate from one who stares the enemy in the eye - who sees the implications of his action or reaction. The enemy becomes objectified - a common complaint of humanists who prefer that people are individuated from being objects or groups and so the repercussions of violence are better grasped: when the enemy is objectified, the morality of interaction becomes opaque and so the just or ethical principles of combat (or action towards others generally) is lost.

Further questions:

Should the evidence of the effects of aerial bombing be at all employed in ethical discussion of its use?

Is aerial bombing so inherently potentially indiscriminate that it ought not to be used at all in warfare?

How have military authorities justified aerial bombing? Have their reasons altered?

Would it be justified to use aerial bombing against 'superior forces' in self-defence?


Douhet, G.
Horne, Alastair. 1940: The Fall of France.
Grayling, A.C. Among the Dead Cities
Green, L.C. (1996) The Contemporary Law of Armed Conflict. Manchester University Press: Manchester.

Article by Dr Alexander Moseley
Added Fri, 25 Feb 2011 15:25

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