Source: https://ihl-databases.icrc.org/customary-ihl/eng/docs/v2_cou_us_rule7
Timestamp: 2019-04-25 17:05:40+00:00

Document:
United States, Letter from the Department of the Army to the legal adviser of the US armed forces deployed in the Gulf region, 11 January 1991, § 8(E), Report on US Practice, 1997, Chapter 1.4.
United States, “The Obama Administration and International Law”, speech by the Legal Adviser, US Department of State at the Annual Meeting of the American Society of International Law, Washington DC, 25 March 2010.
The requirement that attacks be limited to military objectives results from several requirements of international law. The mass annihilation of enemy people is neither humane, permissible, nor militarily necessary. The Hague Regulations prohibit destruction or seizure of enemy property “unless such destruction or seizure be imperatively demanded by the necessities of war.” Destruction as an end in itself is a violation of international law, and there must be some reasonable connection between the destruction of property and the overcoming of enemy military forces. Various other prohibitions and the Hague Regulations and Hague Convention IX further support the requirement that attacks be directed only at military objectives.
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 5–3(b)(2); see also Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 56.
United States, Desert Storm – Rules of Engagement, Pocket Card, US Central Command, January 1991, reprinted in Operational Law Handbook, International and Operational Law Department, The Judge Advocate General’s School, United States Army, Charlottesville, Virginia, 1995, pp. 8-7 and 8-8, § 2.
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 8.1.1.
An object that meets the definition of a military objective may be attacked even if the object, such as an electric power plant, also serves civilian functions, subject to the requirement to avoid excessive incidental injury and collateral damage.
United States, Statement by the Secretary of State, Dean Acheson, 6 September 1950, reprinted in Marjorie Whiteman, Digest of International Law, Vol. 10, Department of State Publication 8367, Washington, D.C., 1968, p. 140.
United States, News briefing by Deputy Assistant Secretary of State for Public Affairs, Robert McCloskey, 22 December 1966, reprinted in Marjorie Whiteman, Digest of International Law, Vol. 10, Department of State Publication 8367, Washington, D.C., 1968, p. 426.
United States, Letter dated 17 January 1991 to the President of the UN Security Council, UN Doc. S/22090, 17 January 1991, p. 2.
United States, Department of State, Diplomatic Note to Iraq, Washington, 21 January 1991, annexed to Letter dated 22 January 1991 to the President of the UN Security Council, UN Doc. S/22130, 22 January 1991.
United States, Department of Defense, Final Report to Congress on the Conduct of the Persian Gulf War, 10 April 1992, Appendix O, The Role of the Law of War, ILM, Vol. 31, 1992, p. 644.
In addition to the grave breaches of the Geneva Conventions of 1949, the following acts are representative of situations involving individual criminal responsibility: … (4) aerial bombardment for the deliberate purpose of … destroying protected areas, buildings or objects.
Avoid harming civilian property unless necessary to save US lives. Do not attack traditional civilian objects, such as houses, unless they are being used by the enemy for military purposes and neutralization assists in mission accomplishment.
United States, Desert Storm – Rules of Engagement, Pocket Card, US Central Command, January 1991, reprinted in Operational Law Handbook, International and Operational Law Department, The Judge Advocate General’s School, United States Army, Charlottesville, Virginia, 1995, pp. 8-7 and 8-8, § G.
United States, Manual for Military Commissions, published in implementation of the Military Commissions Act of 2006, 10 U.S.C. §§ 948a, et seq., 18 January 2007, Part IV, § 6(3), p. IV-4.
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(3), p. IV-4.
(3) ATTACKING CIVILIAN OBJECTS. – Any person subject to this chapter who intentionally engages in an attack upon a civilian object that is not a military objective shall be punished as a military commission under this chapter may direct.
United States, Military Commissions Act, 2006, Public Law 109-366, Chapter 47A of Title 10 of the United States Code, 17 October 2006, p. 120 Stat. 2626, § 950v(b)(3).
“(3) ATTACKING CIVILIAN OBJECTS.—Any person subject to this chapter who intentionally engages in an attack upon a civilian object that is not a military objective shall be punished as a military commission under this chapter may direct.
United States, Military Commissions Act, 2009, § 950t(3).
In 1974, at the Lucerne Conference of Government Experts on Weapons which may Cause Unnecessary Suffering or have Indiscriminate Effects, the head of the US delegation stated that “the law of war also prohibits attacks on civilians and civilian objects as such”.
In a declaration on Yugoslavia adopted in 1991, the European Community and its member States, the Union of Soviet Socialist Republics and the United States stated that they were “particularly disturbed by reports of continued attacks on civilian targets by elements of the federal armed forces and by both Serbian and Croat irregular forces”.
European Community, Union of Soviet Socialist Republics and United States of America, Declaration on Yugoslavia, The Hague, 18 October 1991, annexed to Letter dated 21 October 1991 from the Netherlands, the Union of Soviet Socialist Republics and the United States to the UN Secretary-General, UN Doc. A/C.1/46/11, 24 October 1991.
The United States considers the obligations to protect natural, civilian, and cultural property to be customary international law … Cultural property, civilian objects, and natural resources are protected from intentional attack so long as they are not utilized for military purposes.
United States, Department of Defense, Report to Congress on International Policies and Procedures Regarding the Protection of Natural and Cultural Resources During Times of War, 19 January 1993, p. 202.
Do not fire into civilian populated areas or buildings which are not defended or being used for military purposes. [S]chools … will not be engaged except in self-defense. Do not attack traditional civilian objects, such as houses, unless they are being used by the enemy for military purposes and neutralization assists in mission accomplishment.
United States, Desert Storm – Rules of Engagement, Pocket Card, US Central Command, January 1991, reprinted in Operational Law Handbook, International and Operational Law Department, The Judge Advocate General’s School, United States Army, Charlottesville, Virginia, 1995, pp. 8-7 and 8-8, §§ B, C and G.
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 8.5.1.1.
United States, Letter dated 30 January 1991 to the President of the UN Security Council, UN Doc. S/22173, 30 January 1991, p. 2; see also Letter dated 22 January 1991 to the President of the UN Security Council, UN Doc. S/22130, 22 January 1991, pp. 1–2; and Letter dated 8 February 1991 to the President of the UN Security Council, UN Doc. S/22216, 13 February 1991, p. 2.
If identified as a civil aircraft, air transport in flight should not be the object of attack, unless at the time it represents a valid military objective such as when there is an immediate military threat or use. An unauthorized entry into a flight restriction zone might in some conflicts be deemed an immediate military threat. Wherever encountered, enemy civil aircraft are subject to instruction in order to verify status and preclude their involvement … Civil aircraft on the ground, as objects of attack, are governed by the rules of what constitutes a legitimate military objective as well as the rules and principles relative to aerial bombardment. As sources of airlift they may, under the circumstances ruling at the time, qualify as important military objectives. Civil aircraft entitled to protection include nonmilitary state aircraft and a state owned airline. The principle of law and humanity protecting civilians and civilian objects from being objects of attack as such, protects civil aircraft in flight, because civil aircraft are presumed to transport civilians. Such an aircraft is not subject to attack in the absence of a determination that it constitutes a valid military objective.
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 4-3.
United States, Air Force Pamphlet 110-34, Commander’s Handbook on the Law of Armed Conflict, Judge Advocate General, US Department of the Air Force, 25 July 1980, § 2-2.
Civil passenger vessels at sea and civil airliners in flight are subject to capture but are exempt from destruction. Although enemy lines of communication are generally legitimate military targets in modern warfare, civilian passenger vessels at sea, and civil airliners in flight, are exempt from destruction, unless at the time of the encounter they are being utilized by the enemy for a military purpose (e.g., transporting troops or military cargo) or refuse to respond to the directions of the intercepting warship or military aircraft. Such passenger vessels in port and airliners on the ground are not protected from destruction.
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 8.2.3(6).
Civilian passenger vessels at sea and civil airliners in flight are subject to capture but are exempt from destruction. Although enemy lines of communication are generally legitimate military targets in modern warfare, civilian passenger vessels at sea, and civil airliners in flight, are exempt from destruction, unless at the time of the encounter they are being utilized by the enemy for a military purpose (e.g., transporting troops or military cargo) or refuse to respond to the directions of the intercepting warship or military aircraft. Such passenger vessels in port and airliners on the ground are not protected from destruction.
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 8.6.3.
Following investigations by the Secretary-General of the International Civil Aviation Organization (ICAO) into the shooting down of two civil aircraft by the Cuban air force on 24 February 1996, a debate took place on 26 July 1996 in the UN Security Council, during which the United States stated: “Cuba violated the principle of customary law that States must refrain from resorting to the use of weapons against civil aircraft in flight – a principle that applies whether the aircraft are in national or international airspace”. According to the United States, an attack against a civilian aircraft in flight violates elementary considerations of humanity.
United States, Statement before the UN Security Council, UN Doc. S/PV.3683, 26 July 1996, p. 3.

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