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7 Weapons and the Environment

From: Weapons and the Law of Armed Conflict (2nd Edition)

William H. Boothby

From: Oxford Public International Law (http://opil.ouplaw.com). (c) Oxford University Press, 2023. All Rights Reserved. Subscriber: null; date: 30 May 2023

Armed conflict, international — Armed conflict, non-international — International criminal law, victims — Marine environment, protection — Warfare, air — Weapons, chemical — Weapons control — Weapons, conventional

(p. 74) Weapons and the Environment

7.1  Introduction

When any weapon, means, or method of warfare is considered in order to determine its compliance with the law of armed conflict, its impact on the environment must be considered. All States have certain customary law obligations in this field while States that are party to certain treaties have some more specific duties. This chapter will trace the evolution of the law and will seek to explain those obligations.1

Albert Einstein once said, ‘The environment is everything that isn’t me.’2 The EC Treaty indicates that the scope of the environment extends to human beings, natural resources, land use, town and country planning, waste, and water.3 The notion has been interpreted as extending to fauna, flora, and climate4 and the Special Rapporteur has adopted the following provisional definition: ‘“Environment” includes natural resources, both abiotic and biotic, such as air, water, soil, fauna and flora and the interaction between the same factors, and the characteristics of the landscape.’5 When it comes to interpreting the law of armed conflict, conventional and customary, in relation to the environment, the above meanings will not necessarily, of course, apply. Where treaty interpretation is concerned, any definition in the treaty, or any meaning agreed between the parties, will prevail, failing which the ordinary meaning must be given to the term in the context in which it is used.

Environmental damage is a frequent consequence of warfare. Historical examples of major environmental damage during warfare include the flooding of occupied Dutch lands by Germany during World War II and the destruction of the (p. 75) Huayuankow dam in China by Chinese hands in 1938. Reference might also be made to the destruction of forests and vegetation by the United States over extensive areas during the Vietnam War.6 The land that was affected was in what was then South Vietnam, so it is interesting that two of the cited examples consisted of damage to land belonging to the State causing the damage, or to an ally of that State.7

It is a widely held myth that before the negotiation of the United Nations Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques 1976 (ENMOD), there was no law of armed conflict protection of the environment. It is therefore necessary to trace the early treaties and to explain the extent of the protection that they afford.8 The provisions of ENMOD will then be examined, after which the environmental rules in the 1977 Geneva Protocol 1 (AP1) will be discussed. The customary law position will be assessed and the applicability of these rules to non-international armed conflicts will be determined.

7.2  The Position before 1976

7.2.1  Early Texts

It is probably fair to say that in the early texts on the laws of war, relatively little direct attention was paid to environmental protection in armed conflict.9 Some might argue, therefore, that seeking to interpret language in the early texts as providing an early basis for legal protection of the environment as such in time of war would involve the application of meanings or interpretations to the language of the texts which their authors did not really intend. In the early years, the argument would say, the focus of negotiators was directed at the human sufferings of combatants and populations in war and the prime objective was to produce legal rules which would seek to alleviate the misery of the victims. The alternative and preferable view is that it is possible to trace in the early texts a wider concern to diminish the broader calamities of war, and this object found expression in some of the early principles, often expressed in general terms. Seeking now to interpret those broad principles as applying, inter alia, to the environment is not to stretch their intended meaning but, rather, to give specificity to a principle whose origin lay in that wider concern, expressed as it was in broad statements of principle.

It is therefore legitimate to see in the early texts the seed corn of thought that was later to develop into rules related to the environment, but it would not be right to see those rules as indicating particular concern in the minds of nineteenth- and (p. 76) early twentieth-century negotiators and drafters over environmental damage as such.

With this in mind, we should consider the Lieber Code 1863, which stated clearly that military necessity does not permit the infliction of suffering for its own sake, and that it ‘does not admit of the use of poison in any way, nor of the wanton devastation of a district’.10

While the Lieber Code has no status in conventional law, it is indicative of contemporary thought. It is therefore interesting that the prohibition on wanton devastation, which is repeated in somewhat amended form in draft codes and in treaties that were negotiated later, does not specify the precise type of devastation that is being referred to. The word ‘wanton’ implies that the devastation must have been deliberate, while the word ‘devastation’ does not specify the objects to which it refers and is thus potentially capable of a broad interpretation that would include at least elements of what today would be considered the environment.

The reference in the Preamble to the St Petersburg Declaration11 to the only legitimate object of States in war being the weakening of the military forces of the enemy triggers the evolution of the notion that the means that States can adopt of injuring the enemy are not unlimited. That idea was specifically referred to in Article 12 of the Brussels Declaration 187412 and in Article 4 of the Oxford Manual 1880.13

The prohibition of the use of poison is also repeated in the Brussels and Oxford texts and was clearly already customary. It was later included as a specific rule in Article 23(a) of the Regulations annexed to Hague Convention II of 1899 and, likewise, as Article 23(a) of the Regulations annexed to Hague Convention IV of 1907. There is no evidence that this was widely regarded, either then or since, as forming the basis of a protection for the environment as such in times of armed conflict14 but to the extent that possible methods of poisoning an adversary may have an adverse environmental impact, the primary prohibition would have a secondary protective effect.

7.2.2  Hague Peace Conferences 1899 and 1907

There are provisions of the Hague Regulations which ought to be considered carefully, and for these purposes the Regulations annexed to Hague Convention IV 1907, which superseded those attached to Hague Convention II of 1899 for those States participating in both instruments, will be considered here.(p. 77)

The Martens Clause, found in the Preamble to Hague Convention IV,15 usefully makes the point that the mere fact that treaties do not contain specific provision to address particular evils of war does not imply that no protection exists. The clause is in the following terms:

Until a more complete code of the laws of war has been issued, the high contracting Parties deem it expedient to declare that, in cases not included in the Regulations adopted by them, the inhabitants and the belligerents remain under the protection and the rule of the principles of the law of nations, as they result from the usages established among civilised peoples, from the laws of humanity, and the dictates of the public conscience.

To the extent that the protection of the environment is an essential prerequisite to the protection of the inhabitants and/or the belligerents, the environment derives secondary benefit from the clause. For more explicit protection we must look to other provisions.

Article 22 of the Hague Regulations stipulates that the right of belligerents to adopt means of injuring the enemy is not unlimited. Adam Roberts reports Geoffrey Best’s comment: ‘Post-1945 extensions of that principle from its traditional application to enemy persons and properties to the natural environment are no more than logical, given the novel and awful circumstances that have suggested them.’16

The Hague Regulations then state that it is prohibited to ‘destroy or seize the enemy’s property, unless such destruction or seizure be imperatively demanded by the necessities of war’.17 Roberts identifies as a critical question ‘the extent to which the term “property” can be interpreted to encompass public goods (not necessarily under specific ownership) such as common land, forests, the atmosphere, water resources, and the open seas’.18 Property will encompass some items in private ownership that form part of the environment, such as lakes, land, woods, forests, and farmland, while similar objects in public or collective ownership would also clearly be included. The fact that this latter aspect may not have been in the forefront of the minds of those who negotiated the article may not be determinative of a modern interpretation.

This prohibition is a revision of the prohibition of wanton devastation included in the Lieber Code and to which reference was made earlier, so destruction of the enemy’s property, including the environment, is prohibited unless military necessity demands otherwise. Moreover, Article 23(e) prohibits the use of arms, projectiles, or material calculated to cause suffering that is not militarily necessary. To the extent that such suffering may be caused by the direct impact of the weapon on the (p. 78) environment, the rule does, of course, have potential indirect environmental relevance.

7.2.3  1925 Geneva Gas Protocol

The Geneva Gas Protocol19 prohibits the use in war of asphyxiating, poisonous, or other gases, and of all analogous liquids materials or devices, and the use of bacteriological methods of warfare. While originally negotiated primarily to address the horrors of gas warfare as experienced during World War I, the potential for this instrument to protect the environment as well as humans is clear. Indeed, it could be argued that the use of asphyxiating gases was itself an early form of environmental warfare and that the environmental impact of such methods was more direct, if transitory, than indirect.

Adam Roberts reviewed the stated positions of a number of States party to the Protocol in relation to the possibility of reprisal action and concluded ‘it is not yet possible to conclude that the world has moved beyond threats of retaliation as one basis for ensuring observance of the law of war, including in respect of the environment’.20 Environmental reprisals will be considered in section 7.7 of this chapter.

The provisions of the Chemical Weapons Convention 1993 and of the Biological Weapons Convention 1972 will also contribute to the protection of the environment. Both instruments are discussed in Chapter 9 of this volume. In a similar sense, the provisions of Protocol V to the Conventional Weapons Convention 1980 (CCW), elements of Protocol II and Amended Protocol II to the same Convention, and elements of the Ottawa Convention and of the Convention on Cluster Munitions, concern clean-up obligations after a conflict and are therefore of environmental importance. Post conflict clean-up is, however, a topic in its own right considered in Chapter 17 of this volume.

7.3  ENMOD

The ENMOD21 was negotiated at a time when States were becoming increasingly exercised about the impact of armed conflict on the environment. Recent experience and concerns about future developments had contributed significantly to this:

The USA’s widespread use of various methods of forest and crop destruction in Vietnam had been much criticised. Then in early July 1972 US newspapers carried detailed reports (later confirmed before the US Senate) stating that the USA had been attempting to manipulate (p. 79) weather in Indo-China with a view inter alia to muddying or flooding land routes from North Vietnam.22

Against this background, and through the medium of the Conference of the Committee on Disarmament, the text of ENMOD was negotiated. Understandings were issued by the Committee in respect of certain of the Convention’s articles and which assist with its interpretation.

Under the Convention, States party undertake ‘not to engage in military or any other hostile use of environmental modification techniques having wide-spread, long-lasting or severe effects as the means of destruction, damage or injury to any other State Party’.23 In addition, States undertake not to assist, encourage, or induce activities that breach that provision.24 The term ‘environmental modification techniques’ is defined by the treaty to refer to any technique for changing, through the deliberate manipulation of natural processes, the dynamics, composition, or structure of the Earth, including its biota, lithosphere, hydrosphere, and atmosphere,25 or of outer space.26 That is a wide-ranging definition and would seem to cover any action27 to influence28 natural processes. So the deliberate destruction of a natural phenomenon as part of an attack, or in order to locate enemy positions in order then to be able to prosecute an attack or otherwise to deprive the enemy of shelter, would not breach the ENMOD prohibition.29 Tony Rogers considers the distinction between deliberate human manipulation of the (p. 80) natural processes and conventional acts of warfare which may have adverse effects on the environment, and the possible exception for cases of such extensive destruction of ‘for example the tropical rain forest as to cause a climatic change and to lead to the inference that such change was intended’. He prefers the view that a devastating nuclear attack ‘would not readily fall within the purview of the ENMOD convention since the ensuing environmental modification may well be presented as unintended collateral effects’.30 Thomas Faunce suggests that ‘targeting artificial photosynthesis … may well be interpreted as falling within ENMOD protections’ and the AMW Manual refers to dropping a powerful bomb into the crater of a volcano or into the fragile tectonic plates resulting in the ‘outbreak’ of the volcano or an earthquake.31

The meanings of widespread, long-lasting, and severe were clarified somewhat in a Conference Understanding as follows:

  1. (a)  ‘widespread’: encompassing an area on the scale of several hundred square kilometres;

  2. (b)  ‘long-lasting’; lasting for a period of months, or approximately a season;

  3. (c)  ‘severe’: involving serious or significant disruption or harm to human life, natural and economic resources or other assets.

Further language in the Conference Understanding indicates that these interpretations only apply to the use of these terms in ENMOD. This is significant because, as will be seen later in this chapter, similar language is used in Articles 35 and 55 of AP1. These interpretations do not therefore apply to those later provisions, mainly because the latter treaty does not formally adopt them.

In a further Conference Understanding in relation to the term ‘environmental modification techniques’ as defined in Article II, the possible results of such techniques were said to include earthquakes, tsunamis, upset in the ecological balance of a region, changes in weather and climate patterns, changes in ocean currents or the state of the ozone layer, and changes in the state of the ionosphere. This appreciation, considered with the clarification in the first understanding, gives a clear impression of the substantial scale that an event must reach to come within the Convention’s prohibition.

Two additional factors are deserving of mention. The first is that the prohibition in this treaty addresses the use of the environment itself as a weapon.32 Such activities are prohibited to States party; these include the United States, Russia, India, Pakistan, the United Kingdom, and Japan. The second point is that the elements (p. 81) ‘widespread, long-lasting or severe’ are listed in the alternative. Thus, if an environmental modification technique has either widespread, or long-lasting, or severe effects that in turn are the means of causing damage or injury to another State party, the treaty prohibits its military or other hostile use. The treaty only prohibits such activities against another State party; however, this is of course subject to the position at customary law, as any customary rule will bind all States, including States party to the Convention in their dealings with States non-party. Customary law in relation to environmental protection will be addressed in a later section of this chapter.

In summary therefore:

  • •  Uses of environmental modification techniques which are neither military nor hostile are not prohibited.

  • •  Non-damaging, non-injurious environmental modification is not prohibited.

  • •  Collateral damage resulting from an attack that targets a military objective is not included in the treaty’s prohibition.

  • •  Environmental modification that does not have widespread, long-lasting, or severe effects is not prohibited, even if this is done for hostile purposes.

  • •  Similarly, if destruction, damage, or injury is not occasioned to another State party, the prohibition does not apply—environmental modification to clear fog or cloud and thus facilitate targeting is not prohibited.

  • •  But a failure to foresee the extent of the damage or injury occasioned by the environmental modification activity does not excuse the acting State ‘as long as there is a causal nexus between the deliberate act and the result’.33

7.4  Articles 35 and 55 of AP1

While ENMOD was the first treaty to make specific protective provision in relation to the environment, the second followed soon thereafter. The negotiators of AP1 included two important new rules in Articles 35 and 55.34 The first of these is in the following terms: ‘It is prohibited to employ methods or means of warfare (p. 82) which are intended, or may be expected, to cause widespread, long-term and severe damage to the natural environment.’35

Article 55 requires that:

Care shall be taken in warfare to protect the natural environment against widespread, long-term and severe damage. This protection includes a prohibition of the use of methods or means of warfare which are intended or may be expected to cause such damage to the natural environment36 and thereby to prejudice the health or survival of the population.37

Tony Rogers makes the point that Article 35(3) protects the environment at large and not merely the territory of parties to the conflict,38 whereas Article 55 in part deals with the protection of the civilian population against the effects of hostilities, and thus only applies in the limited circumstances referred to in Article 49(3) of AP1 (i.e. where civilians or civilian objects on land are affected).39

The AP1 Commentary asserts that these provisions prohibit any means or method of warfare which is planned, or may be expected, to cause serious environmental damage.40 This is not, of course, an accurate restatement of the language used. The AP1 Commentary then suggests that the 1976 Convention and the Protocol, taken together, prohibit ‘any method of conventional or unconventional warfare which, by collateral effects, would cause widespread and severe damage to the natural environment as such, whenever this may occur over a period of decades’.41

It was observed earlier that the three elements of ‘widespread, long-term, and severe’, though somewhat similar to those used in ENMOD, have a different meaning in AP1.42 The AP1 Commentary offers the following:(p. 83)

The time or duration required (i.e. long-term) was considered by some to be measured in decades. References to twenty or thirty years were made by some representatives as being a minimum. Others referred to battlefield destruction in France in the First World War as being outside the scope of the prohibition . . . It appeared to be a widely shared assumption that battlefield damage incidental to conventional warfare would not normally be proscribed by this provision. What the article is primarily directed to is thus such damage as would be likely to prejudice, over a long term, the continued survival of the civilian population or would risk causing it major health problems.43

The final sentence of the extract from the Rapporteur’s report would seem to give a helpful indication as to the preferred interpretation of the articles. It indicates that really very severe environmental damage is required for the rule to be broken. Only if the survival or health of the population, as opposed to individual members of it, is prejudiced will the treaty threshold have been reached.44

While of course each article should be interpreted in its own right, in a statement made during the negotiations, the United Kingdom made it clear that ‘we shall interpret [Article 35(3)] in the same way as [Article 55] which in our view is a fuller and more satisfactory formulation’.45

The UK Manual concludes that the only difference of substance between the articles is that while Article 35 relates to all methods of warfare on land, sea, or in the air and irrespective of where in the world they are utilized, ‘article 55 only relates to environmental damage on the territory or in the territorial sea of a State party to the conflict’.46 Importantly, the UK Manual points out that:

these provisions do not automatically prevent certain types of military objectives such as nuclear submarines or super tankers from being legitimate targets nor do they automatically prevent the use of certain means of warfare such as herbicides or chemical agents. The effects of attacking these targets or using these means must be considered.47

(p. 84) 7.5  Environmental Concerns and the Gulf War 1990–1

A detailed analysis of the actions taken by either party to the Gulf War 1990–1 as they affected the environment lies outside the intended scope of this book. Reference may, however, sensibly be made to certain events in order to illustrate and perhaps clarify the law as discussed in this chapter. Thus it is suggested that allied commanders decided not to attack certain Iraqi super-tankers operating in breach of UN Security Council Resolution 665, and that this decision was attributable to the likely environmental result of such attacks.48 While attacks on super-tankers are not explicitly prohibited, the international law rules outlined above would regulate any such attack.49

The opening of the oil valves in Kuwait and in Iraq in January 199150 and the burning of possibly as many as 700 Kuwaiti oil wells during the following month caused major environmental pollution.51 The impact on the atmosphere adversely affected agriculture and the health of local civilians.52 However, it has been suggested that in the event, owing to factors not controlled by Iraq, the long-term environmental consequences were not as bad as had seemed likely.53

In discussing whether the Iraqi actions would be in breach of Article 35(3) if that provision had applied to Iraq during the conflict, it is suggested that while the widespread and severe tests would have been satisfied, the long-term element was probably not breached.54

There are, of course, other articles of AP1 of relevance to environmental protection during armed conflict, for example Articles 52 and 56. These articles are discussed in Chapter 4 of this volume but their application to the environment will not be considered further as they lie outside the main focus of this book.

(p. 85) 7.6  AP1 Environmental Rules and Nuclear Weapons

On ratification of AP1, the United Kingdom made the statement reproduced at section 6.4 of this chapter. The States referred to in section 6.7 made statements in similar terms. As we have seen, the only previous treaty to have made any direct reference to the environment was concerned with hostile use of environmental modification techniques. Articles 35(3) and 55 of AP1 were primarily concerned, rather, with methods or means of warfare that, by collateral effects, would cause the environmental damage referred to in the text. There were no existing specific rules relating to this at the time of the negotiation of AP1, so these were new rules that must be subject to the statements mentioned earlier. The articles do not, therefore, apply to nuclear weapons so far as the United Kingdom and other NATO States ratifying subject to similar statements are concerned.55

7.7  Reprisals

For completeness, brief mention should be made of the position concerning reprisals against the natural environment. The meaning of reprisals was explained in section 4.4 of this volume. Article 55(2) of AP1 prohibits attacks against the natural environment by way of reprisal. While it is a matter of interpretation, it would seem that this does not apply to attacks directed at some person or at some object not comprised in the natural environment but which has a collateral environmental impact. It is also difficult to conclude that it prohibits attacks on the natural environment when the environment itself has become a military objective.

The prohibitions on reprisal action, including this prohibition, were, however, the subject of a lengthy UK statement on ratification of AP1 discussed in section 4.4 of this volume.

On a different but related point, the power of reprisals to modify behaviour should not be entirely discounted. Adam Roberts suggests that the fear of reprisals played some part in the non-use of chemical weapons in World War II56 and by Iraq in the Gulf War 1990–157 and that the threat of retaliation helped to buttress the 1925 Protocol regime.

(p. 86) 7.8  ICRC Guidelines for Military Manuals

In 1996, the International Committee of the Red Cross (ICRC) produced Guidelines58 for military manuals and for instructions to the armed forces on the protection of the environment during armed conflict. These had been preceded by reports published by the ICRC following examination of the issue of environmental protection in periods of conflict. The ICRC had concluded that existing law, if properly implemented, was capable of providing adequate protection.59 Further consideration was then given to the issue60 and the cited Guidelines were the outcome of that work. Interestingly, the UN General Assembly, to which they were submitted, decided in its forty-ninth session not formally to approve them but rather to invite States to ‘give due consideration’ to their incorporation into military manuals and instructions.

In introducing the Guidelines in the International Review of the Red Cross, Hans-Peter Gasser writes ‘they are nothing more and nothing less than a summary of the existing applicable international law rules which must be known and respected by members of the armed forces’,61 which suggests that the text contains what the ICRC regards as generally accepted, customary rules, an impression that is supported by the reference62 to them being ‘drawn from existing international legal obligations’. The text also, however, contains the following: ‘To the extent that the Guidelines are the expression of international customary law or of treaty law binding a particular State, they must be included in military manuals and instructions on the laws of war. Where they reflect national policy, it is suggested that they be included in such documents.’63

This therefore makes it clear that the Guidelines are not necessarily purporting to articulate law applicable to all States on a customary basis, although some of the statements in them will be regarded by the ICRC as having that status. Rather, they express custom and treaty law, and as different States may well have different positions in relation to particular treaty rules, it remains for each State to determine what conventional law applies to it, and its understanding of that conventional law.

On this interpretation of the status of the Guidelines, therefore, States will wish to take note of their contents, very much as the UN General Assembly appears to have done, to derive assistance from them where possible, but to ensure that military manuals and instructions that each State issues accord with its own interpretation of the law applicable to it. This seems to be the basis on which rules grounded in Articles 35(3), 55, and 56 of AP1, for example, which do not in the author’s view yet have customary status, are nevertheless included in the text.

(p. 87) 7.9  ICRC Customary Law Study

The ICRC Customary Law Study Report64 devotes three rules to the natural environment. The first of these65 applies the general principles on the conduct of hostilities to the natural environment and is therefore unobjectionable.

The rule is then broken down into specific stipulations. The first states that no part of the natural environment may be attacked, unless it is a military objective.66 The general prohibition on wanton devastation and the customary rule that attacks be limited to military objectives would seem to support the suggested rule. The second element in the rule states that destruction of any part of the natural environment is prohibited unless required by imperative military necessity.67 That would appear to the author to be a somewhat optimistic formulation. It is the word ‘imperative’ which seems to take the suggested rule too far. With the omission of that word, the rule would, it is suggested, be less controversial and, indeed, largely a restatement of the first element of the rule.

Less controversially, the third element of Rule 43 prohibits ‘[l]aunching an attack against a military objective which may be expected to cause incidental damage to the environment which would be excessive in relation to the concrete and direct military advantage anticipated’. For the purposes of this paragraph of the rule it is assumed that the reference to the environment means in fact the natural environment. Secondly, it is assumed that this rule only applies where the part of the natural environment to be damaged is not itself a military objective. Subject to these assumptions, this paragraph would in some respects seem to be acceptable as a statement of a customary rule, although the author prefers the formulation in Article 8(2)(b)(iv) of the Rome Statute of the International Criminal Court: ‘Intentionally launching an attack in the knowledge that such attack will cause . . . widespread, long-term and severe damage to the natural environment which would be clearly excessive in relation to the concrete and direct overall military advantage anticipated . . . ’

The second rule in the ICRC Study addressing the natural environment requires that methods and means of warfare be employed:

with due regard to the protection and preservation of the natural environment. In the conduct of military operations, all feasible precautions must be taken to avoid, and in any event to minimise, incidental damage to the environment. Lack of scientific certainty as to the (p. 88) effects on the environment of certain military operations does not absolve a party to the conflict from taking such precautions.68

The first of these sentences is correct, it being understood that it does not prohibit attacks on elements of that environment if they become military objectives. The second sentence, subject to the same caveat, must also be right. The third sentence of the rule seems rather optimistic as a statement of customary law. The United Kingdom’s stated position is that the risk of environmental damage must be assessed objectively on the basis of the information available at the time.69 Thus while the obligation to take precautions may continue to apply, the assessment as to whether environmental consequences are to be expected must be made by reference to the information then available.

Tony Rogers addresses the point by discussing the attacks on the Iraqi nuclear and chemical facilities during the Gulf War in 1991.70 He cites a parliamentary answer71 that precautions were taken to prevent the escape of dangerous forces and notes that the USAF attacks on Iraqi nuclear power stations did not create a risk of radioactive contamination.72 He continues:

Attacks on power stations are justified if they are military objectives. The only difference in the case of nuclear power stations is the risk of radioactive contamination. If a power station can be attacked in such a way that there is no such risk, the attack is lawful. Even if radioactive material escapes, it would then be a question of proportionality: how severe the pollution caused and its effects on the civilian population and the environment.73

Rule 45 of the ICRC Study, at sentence 1, reproduces the AP1 Article 35(3) rule. There is a division of opinion among experts as to the customary status of this rule. Some experts consider that Article 35(3) is now customary while other commentators, including the author, noting that certain States decline to be party to AP1 specifically, inter alia, because of this provision, consider that it is not customary.74 (p. 89) Nevertheless, it is worthy of note that the United States accepts the requirement to include expected environmental impact in the proportionality assessment of a proposed attack.75 Furthermore, the Commentary to Rule 45 notes that France, the United Kingdom, and the United States are specially affected as far as the possession of nuclear weapons is concerned, that they have consistently objected to the application of the rule to nuclear weapons, and that ‘if the doctrine of “persistent objector” is possible in the context of humanitarian rules, these three states are not bound by this specific rule as far as any use of nuclear weapons is concerned’.76 As Yoram Dinstein has commented, while a persistent objector who objects ab initio to a new customary rule cannot be held to be bound by it, the notion of ‘states whose interests are specially affected’ is such that if several thereof object, no customary rule can emerge. Professor Dinstein’s analysis is compelling.77

The second sentence of Rule 45 does not refer to Article 1(1) of ENMOD. The result is a statement in the black letter ICRC-proposed rule that omits the ENMOD reference to widespread, long-lasting, or severe damage. Accordingly, while basing a customary rule on the ENMOD text may have been seen by some at least as a ‘progressive’ statement of customary law—not least as ENMOD is not universally ratified—the ICRC black letter formulation would appear to have gone even further and is, on this basis, likely to prove controversial.

It is therefore considered that the current position at customary law is somewhat less advanced than the ICRC Study would indicate. It would, further, seem that any statement of a customary rule must exclude nuclear weapons. On this basis and with a great deal of hesitation, the following provisional formulation is offered as a basis for considering the lawfulness of weapons, methods, and means of warfare in relation to the environment.

The general principles as to the conduct of hostilities apply to the natural environment. To the extent that it, or an element of it, is not a military objective, the natural environment, or that part of it, may not be made the object of attack. Destruction of the natural environment is only permitted to the extent that it is militarily necessary. It is prohibited intentionally to launch an attack knowing that it will cause widespread, long-term, and severe damage to the natural environment that would be clearly excessive in relation to the concrete and direct overall military advantage anticipated. To the extent that the natural environment is not a military objective, methods and means of warfare must be employed and operations must be planned with due regard78 to its protection and preservation and all feasible (p. 90) precautions must be taken to avoid, and in any event to minimize, incidental damage to it.

In relation to the procurement of weapons, the correct conclusions would appear to be that the ENMOD rules prohibit the acquisition of means of warfare which employ environmental modification techniques of the sort referred to in Articles I(1) and II of the 1976 Convention. These rules will, of course, only bind States party to that Convention. For States party to AP1, and subject to any particular declared basis for ratifying that instrument, that treaty does not automatically prohibit the use of certain means of warfare such as herbicides or chemical agents. The generic effects to be expected from the use of weapons must, however, be considered in order to determine whether they ‘may be expected’ to breach the Article 35(3) criteria. For States not party to AP1, the legal position remains as described earlier in this chapter.

The reader may well, having considered the foregoing, come to the conclusion that: ‘After all, in armed conflict, damage to the environment in one form or another—as unpleasant and unplanned as that may be—is virtually inevitable. The consideration of environmental protection during armed conflict will only be taken seriously if viewed in terms of its connectivity to other priorities and concerns.’79

7.10  Peacetime Environmental Law in Armed Conflict

Views diverge among scholars as to the applicability of peacetime environmental treaties during periods of armed conflict.80 There can be little doubt that treaties that expressly provide for their continued application during armed conflict will so apply. It may be that provisions that are compatible with a continued state of armed conflict will also continue to apply. States would not seem, however, to have accepted the application in armed conflict of more general obligations of environmental law, such as the ‘polluter pays’ principle. While some commentators criticize the absence from AP1 of a principle along the lines of the precautionary principle,81 Tony Rogers has suggested that the words ‘or may be expected’ in Article 35(3) would appear to incorporate a precautionary element.82 (p. 91)

While that which may be expected must indeed be considered, it seems clear that the precautionary approach as understood in environmental law is not yet a customary requirement in relation to the use of weapons in armed conflict. Weapons legality issues are determined by reference to the state of scientific understanding at the time the assessment is made. That does not, of course, exclude the possibility that a further evaluation of the acceptability of a weapon may be required if scientific understanding of its characteristics materially changes following its acquisition.

Where post-conflict clearance is concerned, it is doubtful that States in general would acknowledge an obligation, having used force in the limited circumstances provided for in the UN Charter, thereafter to clear all pollutants left anywhere as a result of their military activities.83

7.11  Conclusion

Environmental protection during war has clearly come a long way since the pre-1976 era of applying general principles by analogy. States will determine how they interpret the international law obligations they have accepted in relation to the environment. Customary rules, for which suggested language was offered earlier, will inevitably be limited by what constitutes the general practice of States accompanied by opinio juris. Notwithstanding the writings of learned commentators, States seem likely to continue to be cautious in this respect.

If interpretation of treaty obligations is a matter for States, so also are decisions as to the acceptability of battlefield pollution during future conflicts. While the current law expresses prohibitions by reference to grave and enduring levels of pollution and damage, it is an open question whether these standards can be expected to change over time.84 If environmental protection in the peacetime context is attracting greater attention of States, it is foreseeable that acceptable standards in war will be more restrictively expressed in future and that weapons design will need to take that factor increasingly into account.85 The environment is now widely regarded as a civilian object with the obvious consequence that targeting and weapons law rules directed at protecting civilian objects will apply to it, except to the extent it becomes a military objective.86


1  For useful general discussions see M. N. Schmitt, ‘Green War: An Assessment of the Environmental Law of International Armed Conflict’ (1997) 22 Yale JIL 1, 52–62 and, by the same author, ‘Humanitarian Law and the Environment’ (2000) 28 Denver JILP 265.

2  J. Thornton and S. Beckwith, Environmental Law, (2004), para. 1.002. Environmental protection during armed conflict should not be seen as wholly separate from wider concerns for human existence: P. J. Richards and M. N. Schmitt, ‘Mars Meets Mother Nature: Protecting the Environment during Armed Conflict’ (1998–9) 28 Stetson Law Review 1047, 1051, note 6; in Y. Sandoz, ‘Protection of the Environment in Time of War’, UNIDR News, l July 1992, 12, ‘[t]he concept of the environment should be understood in the widest sense to cover the biological environment in which a population is living. It does not consist merely of the objects indispensable to survival . . . but also includes forests and other vegetation . . . as well as fauna, flora and other biological or climatic elements.’

3  Arts. 174(1) and 175(2).

4  Thornton and Beckwith (n. 2), para. 1.002.

5  Preliminary Report of the Special Rapporteur on the Protection of the Environment in Armed Conflict, UNGA A/CN.4/674 dated 30 May 2014, para. 86.

6  Consider e.g. M. Bothe et al., ‘International Law Protecting the Environment during Armed Conflict: Gaps and Opportunities’ (2010) 879 IRRC 569, 571–2.

7  Richards and Schmitt (n. 2), 1052.

8  See generally G. Best, ‘Historical Evolution of Cultural Norms Relating to War and the Environment’ in A. H. Westing (ed.), Cultural Norms, War and the Environment (1988), 18, 20.

9  ‘At the most basic cultural and linguistic level, the term “environment” did not begin to emerge as a separate category of concern in common parlance until the late 1960s’: Richards and Schmitt (n. 2), 1053.

10  Instructions for the Government of Armies of the United States in the Field, dated 24 April 1863.

11  Declaration Renouncing the Use in Time of War of Explosive Projectiles under 400 Grammes Weight 1868.

12  Project of an International Declaration concerning the Laws and Customs of War, Brussels, 27 August 1874, Art. 12.

13  The Laws of War on Land, Oxford, 9 September 1880 (Oxford Manual). Neither this document, nor the Brussels Declaration, was adopted by States but both provide useful indications of the evolution of informed thinking on these issues.

14  A. Roberts, ‘The Law of War and Environmental Damage’ in C. Bruch and J. Austin (eds.), The Environmental Consequences of War: Legal, Economic and Scientific Perspectives (2000), 52.

15  Preamble to Convention (IV) respecting the Laws and Customs of War on Land 1907, para. 8.

16  Roberts (n. 14), 52 citing Best (n. 8).

17  Hague Regulations 1907, Art. 23(g). The Air and Missile Warfare (AMW) Manual finds a rule that ‘the destruction of the natural environment carried out wantonly is prohibited’, noting that wanton means that the destruction is the result of a deliberate act taken maliciously, i.e. that cannot be justified by imperative military necessity: AMW Manual, Rule 88 and the associated Commentary, para. 2; see also the Tallinn Manual on the International Law Applicable to Cyber Warfare, 2013 (Tallinn Manual), Commentary accompanying Rule 83, para. 5 and note the US Department of Defense (DoD) Law of War Manual, June 2015, para. 5.5.6.

18  Roberts (n. 14), 57.

19  Geneva Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare, 17 June 1925.

20  Roberts (n. 14), 56.

21  For a contextual analysis of ENMOD, see A. H. Westing (ed.), Environmental Warfare: A Technical, Legal and Policy Appraisal (1984).

22  A. Roberts and R. Guelff, Documents on the Laws of War, 3rd edn (2000), 407. There is of course an important distinction to be drawn between using environmental characteristics to enhance a party’s own military performance and using the environment as a weapon; consider the High-Frequency Active Auroral Research Program which uses an array of 180 antennae to project radio energy into the ionosphere and thus tweak disturbances that cause movement in the aurora borealis with the aim of reducing or modulating radio interference: D. Hambling, ‘Weatherwatch: Taming the Aurora’, The Guardian, 11 April 2014, <http://www.theguardian.com/news/2014/apr/11/weatherwatch-aurora-borealis-radio-radar-interference>.

23  ENMOD, Art. I(1). While a breach of the Convention will involve destruction, damage, or injury suffered by another State party (and presumably party to the conflict), the prohibited environmental manipulation may have been caused to the environment in general, i.e. irrespective of national borders.

24  ENMOD, Art. I(2).

25  As to whether herbicide use may come within the Art. II definition, see A. Bouvier, ‘Protection of the Natural Environment in time of Armed Conflict’ (1991) 285 IRRC 563; and W. Krutsch, E. Myjer and R. Trapp (eds.), The Chemical Weapons Convention: A Commentary (2014), 56.

26  ENMOD, Art. II.

27  This is subject to the proviso, of course, that the action must be deliberate.

28  An example of such influencing would be an attempt to modify the weather, e.g. to cause floods or a drought: P. J. Rowe, Defence: the Legal Implications (1987), 117. The Manual of the Law of Armed Conflict, UK Ministry of Defence (2004) (UK Manual), at para. 5.28.1 notes that the Convention is concerned with the deliberate manipulation of the environment for hostile purposes. Note however a statement on ratification made by the Republic of Korea on 2 December 1986 that any technique for deliberately changing the natural state of rivers falls within the term ‘environmental modification techniques’ for the purposes of the Convention and that military or any other hostile use of such techniques that could cause flooding, inundation, reduction in the water level, drying up, destruction of hydrotechnical installations or other harmful consequences comes within the scope of the Convention provided it meets the criteria set out in Art. 1.

29  See further P. C. Szasz, ‘Study of Proposals for Improvements to Existing Legal Instruments relating to the Environment and Armed Conflicts’, paper for the Ottawa Conference of Experts, July 1991; and J. Goldblat, ‘The ENMOD Convention: A Critical Review’ (1993) 2 Humanitäres Vőlkerrecht Informationsschriften 82.

30  A. P. V. Rogers, Law on the Battlefield, 3rd edn (2012), 214 and for criticism of the treaty requirement for hostile intent, see T. Smith, ‘Criminal Accountability or Civil Liability’ in N. Quénivet and S. Shah-Davis (eds.), International Law and Armed Conflict (2010), 95, 101–2.

31  T. Faunce, ‘Nanotechnology and Military Attacks on Photosynthesis’ in H. Nasu and R. McLaughlin (eds.), New Technologies and the Law of Armed Conflict (2014), 175, 187; and AMW Manual, Commentary accompanying Section M, para. 4.

32  In A. H. Westing, ‘The Environmental Modification Convention of 1977: Reflections in Anticipation of the Second Review Conference’ (1992) 5(2) Humanitäres Vőlkerrecht Informationsschriften 70, there is a suggestion that reasonable expectation, as well as intent, ought to be covered by the text, on the basis that intent may be difficult to establish. It is, however, the ordinary meaning of the words used in the treaty text that should inform interpretation, so that deliberate activity committed with intent is what the treaty addresses.

33  Y. Dinstein, The Conduct of Hostilities under the Law of International Armed Conflict, 2nd edn (2010), 199–201.

34  It seems clear that the negotiation of these provisions owes much to certain US operations during the Vietnam War, specifically involving the use of herbicides: W. Hays Parks, ‘Air War and the Law of War’ (1990) 32(1) The Air Force Law Review 1, 86 and note 276 citing statements of Hungary and North Vietnam. Hays Parks cites former US delegation members as concluding the provision would have minimal impact on US military operations (presumably in the event of US ratification of the Protocol) because long-term was considered to be measured in decades, with twenty to thirty years as a minimum, and because of what appeared to be a widely held assumption that battlefield damage incidental to conventional warfare would not normally be proscribed by the provision (ibid., 87). See also Bothe et al. (n. 6), 576.

35  AP1, Art. 35(3).

36  Suggestions that these AP1 rules prohibit also the use of the environment as a weapon (e.g. in A. Bouvier and H. P. Gasser, ‘Protection of the Natural Environment in Time of Armed Conflict’, Paper for the Ottawa Conference of Experts, July 1991) would seem to be consistent with the wording of the provisions themselves, provided, of course, that the damage threshold and, where appropriate, the mental element specified in the respective articles are present.

37  AP1, Art. 55(1). On ratification of the treaty, the United Kingdom made a statement that both provisions ‘cover the employment of methods and means of warfare and that the risk of environmental damage falling within the scope of these provisions arising from such methods and means of warfare is to be assessed objectively on the basis of the information available at the time’: see statement (f) on ratification of AP1 by the United Kingdom on 28 January 1998. The requirement to take ‘care’ would seem to imply a need to take reasonable steps: K. Hulme, ‘Taking Care to Protect the Environment against Damage: A Meaningless Obligation?’ (2010) 879 IRRC 675, 680.

38  Rogers (n. 30), 215.

39  Ibid. Richards and Schmitt (n. 2) 1063: ‘A review of the negotiating record suggests that this ambiguous approach was intended to satisfy two competing camps, those who advocated the intrinsic value approach of Article 35(3), and their opponents who advocated framing restrictions in human terms’. Karen Hulme interprets Art. 35(3) as sitting comfortably beside the most fundamental norms regulating means and methods whereas Art. 55’s reference to risk to the human population reminds us why the prohibition exists: Hulme (n. 37), 677.

40  Commentary on the Additional Protocols of 8 June 1977 to the Geneva Conventions of 12 August 1949, ICRC (AP1 Commentary), para. 1440.

41  Ibid., 1453(c). In so far as this statement in the AP1 Commentary refers to unconventional warfare, it should be borne in mind that Arts. 35(3) and 55 were new rules introduced by the Protocol to which the nuclear statements made by the UK and other NATO countries would accordingly apply.

42  The Federal Republic of Germany made a statement to this effect during negotiations, reported in the AP1 Commentary, para. 1459. The difference of meaning, and indeed the relative absence of an authoritative precise interpretation for the words as used in AP1, has been rightly criticized as a major shortcoming, and has led individual States to try to fill the gap: Richards and Schmitt (n. 2), 1065–6. For a discussion of the meanings of the terms in their respective treaty contexts, see H. S. Levie, ‘The 1977 Protocol 1 and the United States’ (1993–4) 38 St Louis ULJ 469, 477–9.

43  Rapporteur’s Report CDDH/215/Rev.1, para. 27 reported in AP1 Commentary, para. 1454. In the same paragraph of the AP1 Commentary, the point is made that these rules were not intended to cover damage ordinarily caused by conventional means and methods of warfare. See also L. Doswald-Beck, ‘The Value of the 1977 Protocols’ in M. A. Meyer, Armed Conflict and the New Law (1989), 162.

44  See S. Witteler, ‘Der Krieg im Golf und seine Auswirkungen auf die natürliche Umwelt: Notwendige überlegungen zu den umweltschützenden Vorschriften des humanitären völkerrechts’ (1991) 4(1–2) Humanitäres Vőlkerrecht Informationsschriften 48; and P. Antoine, ‘International Humanitarian Law and the Protection of the Environment in Time of Armed Conflict’ (1992) 32 IRRC 526.

45  CDDH/SR.39, Annex, 118 reported in AP1 Commentary, 420, note 131.

46  UK Manual, 76, para. 5.29.1. Consider, however, the suggestion that the US use of Agent Orange during the Vietnam War would have breached Art. 55: D. Thürer, International Humanitarian Law: Theory, Practice, Context (2011), 84.

47  UK Manual, para. 5.29.3.

48  G. van Hegelsom, Brussels Congress (1991).

49  See H. P. Gasser, ‘Some Legal Issues Concerning Ratification of the 1977 Geneva Protocols’ in M. A. Meyer (ed.), Armed Conflict and the New Law (1989), 91–2 but consider also E. Rauch, The Protocol Additional to the Geneva Conventions for the Victims of Armed Conflicts and the United Nations Convention on the Law of the Sea: Repercussions on the Law of Naval Warfare (1984), 143–51.

50  US DoD Report, Conduct of the Persian Gulf War, Final Report to Congress (April 1992), 624; A. R. G. Price, Possible Environmental Threats from the Current War in the Gulf (1991); and R. J. Zedalis, ‘Military Necessity and Iraqi Destruction of Kuwaiti Oil’ (1990) 2 Revue Belge de Droit International 333, 333–4.

51  Statement by Tony Baldry MP, Parliamentary Under-Secretary of State for the Environment, Hansard (Commons) 15 March 1991, col. 1387.

52  P. Painchaud, ‘Environmental Weapons and the Gulf War’, Paper for the Ottawa Conference of Experts (1991).

53  The Times, 8 May 1991. Tony Rogers comes to the conclusion that, at any event, it is arguable whether the techniques employed were those envisaged by the ENMOD Convention. Noting various suggestions as to why the action was taken by Iraq, see e.g. J. Arnold MP, Hansard (Commons) 15 March 1991, col. 1365; and A. Roberts, ‘Failures in Protecting the Environment’ in P. J. Rowe (ed.), The Gulf War 1990–91 in International and English Law (1993 in which he implies that the Iraqi actions seem to have violated the Hague Regulations, Art. 23(g); Tony Rogers goes on to suggest that the Iraqi activities may amount to a breach of Art. 53 of the Third Geneva Convention, and thus a grave breach of the same instrument, as provided for in art 129: Rogers (n. 30), 228.

54  Rogers (n. 30), 230. See also Tam Dalyell MP, Hansard (Commons) 15 March 1991, cols. 1337–9 commenting on other sources.

55  The new environmental damage rule was not designed to take into account nuclear weapons: F. Kalshoven and L. Zegveld, Constraints on the Waging of War, 4th edn (2011), 118.

56  Roberts (n. 14), 54.

57  A. Roberts, ‘The Laws of War in the 1990–91 Gulf Conflict’ (1993–4) 18(3) International Security 163–4.

58  Guidelines for Military Manuals and Instructions on the Protection of the Environment in Times of Armed Conflict (30 April 1996) 311 IRRC 230–7.

59  Bouvier (n. 25), 567; and A. Bouvier, ‘Recent Studies on the Protection of the Environment in Time of Armed Conflict’ (1992) 291 IRRC 554.

60  See H.-P. Gasser, ‘For Better Protection of the Natural Environment in Armed Conflict: A Proposal for Action’ (1995) 89 AJIL 637.

61  Guidelines for Military Manuals (n. 58), final paragraph of the introduction.

62  Ibid., para. 1(1).

63  Ibid., para. 1(3).

64  In an article that predated the publication of the ICRC Customary Law Study, the established customary principles of greatest apparent relevance to the environment, military necessity, and discrimination, were assessed, but found ‘unlikely to consistently serve as predictable and reliable constraints on environmental damage during armed conflict’: Richards and Schmitt (n. 2), 1075.

65  ICRC Customary Law Study Report, Vol. 1, 143, Rule 43.

66  Ibid., Rule 43(A). Rule 83(a) of the Tallinn Manual stipulates that ‘the natural environment is a civilian object and as such enjoys general protection from cyber attacks and their effects’, a rule which is stated to have customary status in international armed conflicts and, the majority of the Tallinn Experts felt, in non-international armed conflicts: Commentary accompanying Rule 83, para. 1.

67  ICRC Customary Law Study Report, Vol. 1, 143, Rule 43(B).

68  Ibid., Rule 44, sentences 1 and 2. For a discussion of Rule 44, see Hulme (n. 37), 684–7; and as to the ‘due regard’ element of the rule, see Dinstein (n. 33), 198 where Yoram Dinstein reflects on the implications of the status of the natural environment as a civilian object e.g. for the application of the proportionality principle.

69  UK statement (f) made on ratification of AP1.

70  Rogers (n. 30), 231–2.

71  By Mr Lennox-Boyd, Hansard (Commons) 26 June 1991, col. 487.

72  See evidence of UK Secretary of State, Preliminary Lessons of Operation Granby, House of Commons Defence Committee, Tenth Report, 1991, 11.

73  Rogers (n. 30), 232.

74  AMW Manual, 205, para. 5; Tallinn Manual, Rule 83 and associated Commentary; Memorandum for Assistant General Counsel (International), Office of the Secretary of Defense, 1977 Protocols Additional to the Geneva Conventions: Customary International Law Implications, 8 May 1986.M. J. Matheson, ‘The United States Position on the Relation of Customary International Law to the 1977 Protocols Additional to the 1949 Geneva Conventions’ (1987) 2 AUJILP 419. In J. P. Terry, ‘The Environment and the Laws of War: The Impact of Desert Storm’ (1992) 45(1) Naval War College Review 65 the point is made that more restrictive environmental provisions arouse US concern because they could be implemented only at the expense of otherwise lawful military operations, and the use of fuel-air explosives to attack a target is mentioned. Roberts (n. 14), 70, notes the United States’ ‘history of scepticism about those provisions of Protocol 1 that explicitly mention the environment’ while Greenwood considers ‘while there is likely to be continuing controversy about the extent of the principle contained in article 35(3), the core of that principle may well reflect an emerging norm of international law’: C. Greenwood, ‘Customary Law Status of the 1977 Geneva Protocols’ in A. J. M. Delissen and G. J. Tanja (eds.), Humanitarian Law of Armed Conflict: Challenges Ahead (1991), 102–3, 105. While this may indeed be so, to declare it as a customary rule, which of course Professor Greenwood does not do, would be inaccurate; Dinstein notes that the United States, the United Kingdom, and France are specially affected States such that their opposition to the suggested customary norm has thwarted its formation, at least in relation to nuclear weapons: Dinstein (n. 33), 205. For the most recent US rejection of the rule, see US DoD Law of War Manual, June 2015, para.

75  See e.g. USAF Manual, Air force Operations and the Law: A Guide for Air and Space Forces (2009), 301.

76  ICRC Customary International Law Study Report, Vol. 1, 154–5.

77  Y. Dinstein, ‘The ICRC Customary International Humanitarian Law Study’ (2006) 36 Israel Yearbook on Human Rights 1, 13–14.

78  AMW Manual, Rule 89 and associated Commentary; and see US DoD Law of War Manual, June 2015, para.

79  Richards and Schmitt (n. 2), 1079.

80  See Special Rapporteur’s Preliminary Report (n. 5), paras. 2–3; S. Voneky, ‘Peacetime Environmental Law as a Basis of State Responsibility for Environmental Damage Caused by War’ in J. E. Austin and C. E. Bruch (eds.), The Environmental Consequences of War (2000), 193–4.

81  M. Bothe, ‘The Protection of the Environment in Time of Armed Conflict’ (1991) 34 German Yearbook of International Law 57.

82  Rogers (n. 30), 217. L. Wexler, ‘Limiting the Precautionary Principle: Weapons Regulation in the Face of Scientific Uncertainty’ 39 UC Davis LR (2006) 459 argues for the application of the precautionary principle, specifically during AP1, Art. 36 weapons reviews. Under that principle, where there are threats of serious, irreversible damage, lack of certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation (pp. 464–5 citing the Rio Declaration on Environment and Development, UN Doc. A/CONF.151/5/Rev1, 12 August 1992) but Mr Wexler acknowledges (pp. 489–93) the serious doubts as to its customary status and as to its application in war, its inherent lack of clarity, and doubts as to the level of damage that is required for the principle to be triggered.

83  But consider Voneky (n. 80), 224–5. See also M. N. Schmitt, ‘War and the Environment: Fault Lines in the Prescriptive Landscape’ in J. E. Austin and C. E. Bruch (eds.), The Environmental Consequences of War: Legal, Economic and Scientific Perspectives (2000), 87.

84  In this respect, the ongoing work of the International Law Commission (n. 5), will be of utmost importance.

85  Michael Bothe and others discuss the inadequacy of current international humanitarian law rules for the protection of the environment: see Bothe et al. (n. 6), 571–9, and then consider the potential applicability of international environmental law during armed conflict (pp. 579–91), but after a careful analysis conclude that major uncertainties remain and that greater clarity is required. At the time of writing the environmental criteria that must be applied during armed conflict, however unsatisfactory they may be, remain, for States party to AP1, those in Arts. 35(3) and 55, and for other States, the customary requirements discussed earlier.

86  Hulme (n. 37), 677–8.