Rule 43. The general principles on the conduct of hostilities apply to the natural environment:

1. A. No part of the natural environment may be attacked, unless it is a military objective.

2. B. Destruction of any part of the natural environment is prohibited, unless required by imperative military necessity.

3. C. Launching 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 is prohibited.

Practice

Volume II, Chapter 14, Section A.

Summary

State practice establishes this rule as a norm of customary international law applicable in both international and non-international armed conflicts.

Principle of distinction

The rule that it is prohibited to attack any part of the natural environment unless it is a military objective is based on the general requirement that a distinction be made between military objectives and civilian objects (see Rule 7). This rule is reflected in Protocol III to the Convention on Certain Conventional Weapons, which provides that “it is prohibited to make forests or other kinds of plant cover the object of attack by incendiary weapons except when such natural elements are used to cover, conceal or camouflage combatants or other military objectives, or are themselves military objectives”. The military manuals and official statements which consider that an area of land may be a military objective if it meets the required conditions also reflect this.