The application of the general Rules prohibiting attacks directed against civilians or civilian objects, as well as indiscriminate attacks, is confined to air or missile attacks that entail violent effects, namely, acts resulting in death, injury, damage or destruction.
- Despite the lack of direct authority for this Rule in treaty law, the majority of the Group of Experts concluded that it generally reflects State practice.
- The emphasis in Rule 21 on “acts resulting in death, injury, damage or destruction” is intended to exclude psychological warfare, whether directed against combatants or civilians, which does not generate violent effects. See paragraph 9 of the Commentary on Rule 13 (b).
- By the same token, a CNA which interferes with air traffic control but does not cause any “death, injury, damage or destruction” does not qualify as an attack (see Rule 1 (e) and Rule 1 (m)).
- Rule 21 applies also in non-international armed conflict.