text: Chapter 13
  protected from intentional attack or destruction. However, civilian objects may lose their protections if they
  are being used for military purposes, or there is a military necessity for their destruction or seizure. Civilian
  objects may, in such circumstances, become military objectives, and if so, the law of war permits their
  destruction. In treaties such as Hague IV and its annex and the Geneva Conventions, where an express
  prohibition has been stated, neither military necessity nor any other rationale of necessity may override that
  prohibition. In short, the principle of military necessity authorizes that use of force that is required to
  accomplish the mission, but it does not authorize acts otherwise prohibited by the law of war. This principle
  must be applied in conjunction with other law of war principles as well as other, more specific legal
  constraints set forth in law of war treaties to which the U.S. is a party.
  HUMANITY, UNNECESSARY SUFFERING, OR SUPERFLUOUS INJURY
  13-16. The right of belligerents to adopt means of injuring the enemy is not unlimited, as Hague IV
  Annex, Article 22, states. Article 23(e) then captures the essence of the Law of War principle of humanity
  as it prohibits the employment of arms, projectiles, or material calculated to cause unnecessary suffering.
  The principle of humanity is also called the principle of unnecessary suffering or superfluous injury. The
  terms unnecessary suffering and superfluous injury are regarded as synonymous. Although neither of the
  terms is defined, they are understood to refer to injury to persons, rather than damage to objects. The
  prohibition of unnecessary suffering constitutes acknowledgement that the suffering of combatants is
  lawful and expected, and may include severe injury or loss of life. As a general proposition, the suffering
  inflicted by weapons or munitions would be deemed unnecessary only if—
  * Its use was calculated to cause unnecessary suffering.
  * The inevitable result of the normal use causes an injury the nature of which is considered by
  governments as manifestly disproportionate in relation to the military advantage anticipated
  from employment of the weapons or munitions.
  13-17. Weapons’ or munitions’ effects must be weighed in light of comparable lawful weapons and
  munitions in use on the modern battlefield. A weapon cannot be declared unlawful merely because it may
  cause severe suffering or injury. The appropriate determination is whether a weapon’s or munitions’
  employment for its normal or expected use would be prohibited under some or all circumstances. The
  correct criterion is whether the employment of a weapon for its normal or expected use inevitably would
  cause injury or suffering manifestly disproportionate to its military effectiveness. A state is not required to
  foresee or anticipate all possible uses or misuses of a weapon or munitions, since almost any weapon or
  munition can be misused in ways that might be prohibited.
  13-18. Under the law of war, combatants may kill or wound enemy combatants and civilians taking a
  direct part in hostilities; such acts are legitimate if accomplished with lawful means and methods. For
  example, the prohibition of unnecessary suffering does not limit the bringing of overwhelming firepower
  on an opposing military force in order to subdue or destroy it. What the law of war does prohibit is the
  design, modification, or employment of a weapon or munitions for the purpose of increasing or causing
  suffering beyond that required by military necessity.
  DISCRIMINATION
  13-19. The principle of discrimination, sometimes referred to as the principle of distinction, is the
  international law obligation of parties to a conflict to distinguish between the civilian population (or
  individual civilians not taking a direct part in the hostilities) and combatant forces when engaged in
  military operations, directing the application of force solely against personnel belonging to the latter.
  Similarly, military force may be directed only against military objects or objectives, and not against civilian
  objects. A military objective is not limited to military bases, forces, or equipment, but includes other
  objects that contribute to an opposing state’s ability to wage war. Additionally, a civilian object is immune
  from intentional attack unless and until it loses its protected status through enemy abuse of that status. The
  principle of discrimination also provides civilians immunity from direct attack for as long as they take no
  part in hostile acts against military forces.
  13-20. The principle of discrimination applies to military forces engaged in offensive or defensive
  operations, and to governments providing protection for their civilian population and civilian objects. Each