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Bombing, Ethics of

Bombing, Ethics of. Debate over the ethics of bombing focuses largely on strategic bombing: attacks carried out by strikes into the enemy nation for such purposes as impeding production, disrupting transportation and communications, and lowering civilian support for the war effort. Strategic bombing is morally problematic because by its nature it involves harm (intentional or not) to nonmilitary targets, while tactical bombing aims only at military targets. As originally conceived by Giulio Douhet and Billy Mitchell in the 1920s, strategic bombing was intended to target population centers so as to disrupt the social fabric of the enemy nation and thereby destroy its ability to wage war effectively. Less extreme advocates of airpower, beginning in the 1930s, argued for a conception of strategic bombing by which the actual targets were defined as military bases and means of production, transport, and communication in direct support of military activity, though these might be located in or near population centers.

In terms of ethical analysis, while tactical bombing engages only the ethical principle of proportionality (no destruction beyond that necessary for the tactical purpose), strategic bombing engages both proportion and the principle of discrimination or noncombatant immunity. Two historical contexts have largely focused the ethical debate: the experience of strategic bombing of cities in Britain, Germany, and Japan during World War II, and the development of strategic nuclear targeting in the period 1945–89. Three distinct kinds of ethical argument against such bombing have been advanced.

First is an argument framed in terms of the obligation to protect noncombatants—understood as persons not engaged in the fighting or in providing functional support of the military effort—from direct, intentional harm by acts of war. This is the classic argument from Just War theory, applied long before the age of aerial warfare to earlier forms of attack directed against noncombatant or mixed combatant‐noncombatant targets, such as the artillery bombardment of enemy cities during sieges. The influential early modern theorist Francisco de Vitoria reasoned that this argument accepted bombardment of a fortified city as a sometimes necessary part of just warfare, but insisted that only the fortifications and the combatant forces in such a city can rightly be targeted. Collateral harm to noncombatants is justified only if it is an indirect and unintentional effect of such legitimate acts of war (the “rule of double effect”). The total damage caused must, moreover, not be disproportionate to the justifiable ends achieved. In the seventeenth and eighteenth centuries, such writers as John Locke and Emmerich de Vattel extended the traditional idea of noncombatant immunity to prohibit acts of war aimed at civilian property and values of common benefit to humanity.

The codification of positive international law on war, beginning in the late nineteenth century, incorporated this established ethical understanding of noncombatant immunity. The 1907 Hague Convention IV on land warfare explicitly prohibited attacks or bombardment against undefended “towns, villages, dwellings, or buildings,” and required that “all necessary steps must be taken to spare” various specific kinds of noncombatant property. Similar provisions were laid out in Convention IX on naval bombardment. The 1923 Hague Rules of Aerial Warfare extended these restrictions to aerial bombardment, adding an explicit prohibition of such bombardment “for the purpose of terrorizing the civilian population, of destroying or damaging private property not of military character, or of injuring non‐combatants.” These provisions remain the letter of positive international law on war, though their application has been the subject of both legal and ethical dispute.

Curiously, in the context of World War II, arguments for the need to avoid harm to noncombatants in strategic bombing appear more in debates within military circles than in ethical discussion. A prominent and influential exception was an article (1944) by Fr. John C. Ford, S.J., applying this form of moral reasoning to “obliteration bombing.” Ford's position was essentially that of Vitoria, updated to address strategic air bombardment. In recent ethical debate, such influential thinkers as Paul Ramsey and Michael Walzer have forcefully stated the argument against strategic targeting of noncombatants, with Ramsey—drawing on Ford but giving a new basis to his argument—reasoning from the duty of nonmaleficence, as defined by the Christian ideal of love, and Walzer focusing on the inherent right of noncombatants not to be harmed directly and intentionally by acts of war. Both accept the moral “rule of double effect” that allows genuinely unintended, indirect harm to noncombatants from an otherwise justified act of war, subject to a judgement as to its proportionality. There is some question as to whether bombardment by nuclear weapons can ever meet these tests. For example, the American Catholic bishops in their 1983 pastoral letter explicitly rejected the use of nuclear weapons as inherently causing indiscriminate and disproportionate collateral destruction even when targeted directly at military targets within populated areas. Various authors in recent moral debate have applied similar reasoning to condemn retroactively incendiary and atomic bombing in World War II.

The second line of argument over the ethics of bombing is posed in terms of a proportional calculus of the goods achieved versus those lost and the evils done versus those averted. In contrast to the first line, which depends on an ethical distinction between combatants and noncombatants, this second argument generally assumes that in modern warfare every member of a belligerent society is in some sense complicit and thus may be targeted by acts of war. With the combatant‐noncombatant distinction sharply diminished, or denied altogether, whether and how far to target civilians depends on the relative utility of doing so in prosecuting the war. In practice, this argument typically has reduced the ethical calculus to a counting of the actual or potential lives lost and casualties inflicted by strategic bombing versus the cost in lives and casualties of other military means without such bombing. Such an argument, reflecting Douhet and Mitchell, was widely used in the British and American debate over the strategic bombing of Germany and Japan in World War II (including the use of atomic bombs against Japan, where the decision was explicitly to choose targets of a mixed civilian‐military nature), and it carried over into early debates about American strategic nuclear targeting. Generally, the moral force of this argument lies in the claim that strategic bombing shortens the conflict and therefore saves lives. Thus President Truman justified the atomic bombing of Hiroshima and Nagasaki by its inducing Japan to end the war, reasoning echoed by such recent authors as Paul Fussell and given wide popular voice in the debate over the Enola Gay exhibit at the Smithsonian Institution. In the context of strategic nuclear targeting, deterrence theorists extended this reasoning into the concept that the threat of such bombing by nuclear weapons can prevent the beginning of war.

The third type of argument has been named “supreme emergency” by Walzer. It holds in principle to the morality of the combatant‐noncombatant distinction and other forms of restraint in war, but maintains that a particular threat may be so grave that if the enemy won, these and all other forms of moral order upheld by the vanquished society would be lost. Under such extreme circumstances, it is seen as justifiable to use means that temporarily violate the accepted ethical restraints in order to protect and preserve them for the future. Walzer identifies this as the argument used in justifying the indiscriminate bombing of German cities by British Bomber Command in World War II. However, overtones of similar reasoning can be found in debates over the ethics of nuclear targeting, for example, in early postwar arguments justifying atomic counter‐city strikes to punish the “crime” of aggression, and later arguments over nuclear strategy that took as their premise the moral superiority of the United States over the Soviet Union.

In World War II and during much of the Cold War, the technology of aerial bombardment did not allow for close operational discrimination between combatant and noncombatant targets. In this context, the moral argument based on the combatant‐noncombatant distinction was dismissed by advocates of the second line of argument as an unattainable ideal and thus irrelevant to the actual conduct of war, leaving only moral reasoning based in proportionality. At the same time, so‐called modern war pacifists attacked the first line of argument from another direction, criticizing the rule of double effect as leading in practice to removing the protection of noncombatants living or working close to military targets. For these, too, the critical moral test of targeting doctrine was proportionality.

In contrast to these positions, both international law and contemporary American military doctrine explicitly hold to the combatant‐noncombatant distinction that is central to the first form of ethical reasoning about strategic bombing. The present context, however, has changed significantly as targeting and delivery technology for “smart” bombs and both cruise and ballistic missiles have greatly improved in accuracy, allowing targeting decisions that can realistically discriminate between combatants and noncombatants even when the two are in close proximity. Though on the face of the matter this means that ethical argument depending on a combatant‐noncombatant distinction can no longer be criticized as setting an impossibly high ethical standard for warfare, it is also true that such increased accuracy allows for less destructive warheads, so that the ethical criterion of proportionality is also more likely to be satisfied when such weapons are employed for strategic bombardment.

In the final analysis, the three ethical arguments defined above are not divided by what is operationally possible in any given context, but by sharply differing normative concepts of what matters in the conduct of war. A conception of war in which discrimination between combatants and noncombatants is a binding moral obligation differs fundamentally from one in which all the citizens of the enemy nation may equally be targeted, subject only to concerns of proportionality, and both differ from a conception in which “supreme emergency” may justify temporary suspension of all moral rules for fighting. Thus, ethical debate over strategic bombing may be expected to continue so long as these differing conceptions of war persist.
[See also Bombing of Civilians; Bombs; Strategy: Air Warfare Strategy; Vietnam War, U.S. Air Operations in the; World War II, U.S. Air Operations in.]


Edward Meade Earle, ed., Makers of Modern Strategy, 1943; repr. 1971.
Paul Ramsey , War and the Christian Conscience, 1961.
James Turner Johnson , Ideology, Reason, and the Limitation of War, 1975.
Michael Walzer , Just and Unjust Wars, 1977.
William V. O'Brien , The Conduct of Just and Limited War, 1981.
National Conference of Catholic Bishops , The Challenge of Peace, 1983.
James Turner Johnson , Can Modern War Be Just?, 1984.

James Turner Johnson

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