AFDD 2-1.9, page 100

90 For example, an armored vehicle used in combat is located at a school. The vehicle is a valid target. However, destroying the vehicle with certain types of munitions may place lives and safety of nearby noncombatants in jeopardy. The potential for injury to noncombatants should help guide the choice of munitions and/or other actions chosen against the vehicle. Distinction (Discrimination). Have we distinguished between combatants and non-combatants; have we distinguished between military objectives and protected property or places? The principle, based on customary international law, requires parties to direct operations only against combatants and military objectives. It prohibits “indiscriminate attacks”. For example: Dropping munitions—guided or not—in a residential area without regard to whether there are combatants or military objectives in the area simply because there “might be” adversary forces there would be an indiscriminate attack. The use of gravity-guided munitions (non-precision) against enemy combatants or military objectives is not of itself an indiscriminate attack. LOAC TARGETING RESTRICTIONS Personnel Are we targeting personnel protected under LOAC? Intentional direct attacks on civilians are prohibited. However, this is distinctly different from the incidental injury that may be caused to civilians or civilian objects as a result of an attack on a valid military target (collateral damage). Collateral damage is an issue of proportionality. Protection of the Civilian Population. Civilian populations may not be intentionally targeted for attack. Acts of violence designed to spread terror among the civilian population are prohibited. However, civilians may not be used as “human shields” to protect military targets from attack. The fact that they may be used to do so does not necessarily prevent the military object from being attacked. As directed or time permitting, targets surrounded by human shields will probably need to be reviewed by higher authority for policy and legal considerations based on the specific facts. Protection of Wounded and Sick. Direct attacks on wounded and sick who are no longer contributing to an adversary’s military operations are prohibited by the Geneva Conventions. As noted above, the incidental additional injury that might be caused to sick and wounded still on the battlefield in the proximity to valid military targets is an issue of proportionality. The sick and wounded may also not be used as “human shields” to protect military targets from attack. The fact that they may be used to do so does not necessarily prevent the military object from being attacked. As directed or time permitting, targets surrounded by human shields will probably need to be reviewed by higher authority for policy and legal considerations based on the specific facts.