Related Rule
United States of America
Practice Relating to Rule 1. The Principle of Distinction between Civilians and Combatants
The US Air Force Pamphlet (1976) states: “In order to insure respect and protection for the civilian population and civilian objects, the parties to the conflict must at all times distinguish between the civilian population and combatants.” 
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).
The US Naval Handbook (1995) states: “The law of armed conflicts is based largely on the distinction to be made between combatants and noncombatants.” 
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), § 5.3; see also §§ 8.1 and 11.1.
The US Naval Handbook (2007) states: “The principle of distinction is concerned with distinguishing combatants from civilians and military objects from civilian objects so as to minimize damage to civilians and civilian objects.” 
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, § 5.3.2.
In explaining the US Government’s position on the basic principles applicable in armed conflicts before the Third Committee of the UN General Assembly in 1968, the US representative stated that the principle of distinction, as set out in draft General Assembly Resolution 2444 (XXIII), constituted a reaffirmation of existing international law. 
United States, Statement before the Third Committee of the UN General Assembly, UN Doc. A/C.3/SR.1634, 10 December 1968.
Subsequently, US officials have referred to General Assembly Resolution 2444 (XXIII) as an accurate statement of the customary rule that a distinction must be made at all times between persons taking part in hostilities and the civilian population. 
United States, Letter from J. Fred Buzhardt, General Counsel of the Department of Defense, to Senator Edward Kennedy, Chairman of the Subcommittee on Refugees of the Committee on the Judiciary, 22 September 1972, AJIL, Vol. 67, pp. 122–126; Statement of the Acting Assistant Legal Adviser for Politico-Military Affairs during a symposium at the Brooklyn Law School, 25 September 1982, reprinted in Marian Nash (Leich), Cumulative Digest of United States Practice in International Law, 1981–1988, Department of State Publication 10120, Washington, D.C., 1993–1995, pp. 3421–3422.
In 1991, in response to an ICRC memorandum on the applicability of IHL in the Gulf region, the US Department of the Army pointed out that “the obligation of distinguishing combatants and military objectives from civilians and civilian objects is a shared responsibility of the attacker, defender, and the civilian population as such”. 
United States, Letter from the Department of the Army to the legal adviser of the US Army forces deployed in the Gulf region, 11 January 1991, § 8(E), Report on US Practice, 1997, Chapter 1.4.
In 1992, in its final report to Congress on the conduct of the Gulf War, the US Department of Defense stated that Article 48 of the 1977 Additional Protocol I “is generally regarded as a codification of the customary practice of nations, and therefore binding on all”. 
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. 625.
The US Department of Defense also stated:
The law of war with respect to targeting, collateral damage and collateral civilian casualties is derived from the principle of discrimination; that is, the necessity for distinguishing between combatants, who may be attacked, and noncombatants, against whom an intentional attack may not be directed, and between legitimate military targets and civilian objects. 
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. 621.
According to the Report on US Practice: “It is the opinio juris of the United States that … a distinction must be made between persons taking part in the hostilities and the civilian population to the effect that the civilians be spared as much as possible.” 
Report on US Practice, 1997, Chapter 1.4.
In March 2010, in a speech given at the Annual Meeting of the American Society of International Law, the US State Department’s Legal Adviser stated:
[T]his Administration has carefully reviewed the rules governing targeting operations to ensure that these operations are conducted consistently with law of war principles, including:
- First, the principle of distinction, which requires that attacks be limited to military objectives and that civilians or civilian objects shall not be the object of the attack;
In U.S. operations against al-Qaeda and its associated forces – including lethal operations conducted with the use of unmanned aerial vehicles – great care is taken to adhere to these principles in both planning and execution, to ensure that only legitimate objectives are targeted. 
United States, “The Obama Administration and International Law”, Speech by the Legal Adviser of the US Department of State given at the Annual Meeting of the American Society of International Law, Washington DC, 25 March 2010.
[emphasis in original]
The US Rules of Engagement for Operation Desert Storm (1991) sets as a basic rule “fight only combatants”. 
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, § 1.
The US Naval Handbook (1995) states that only attacks against combatants and other military objectives are lawful. 
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.
The US Naval Handbook (2007) states: “Only military objectives may be attacked. Military objectives are combatants … ”. 
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, § 8.2.
The Handbook also states: “Lawful combatants … are subject to attack at anytime during hostilities unless they are hors de combat.” 
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, § 8.2.1.
At the CDDH, the United States stated that the first sentence of Article 47(2) of the draft Additional Protocol I (now Article 52(2)) “prohibits only such attacks as may be directed against non-military objectives. It does not deal with the question of collateral damage caused by attacks directed against military objectives.” 
United States, Statement at the CDDH, Official Records, Vol. VI, CDDH/SR.41, 26 May 1977, p. 204.
In March 2010, in a speech given at the Annual Meeting of the American Society of International Law, the Legal Adviser of the US State Department stated:
Recently, a number of legal objections have been raised against U.S. targeting practices. …
First, some have suggested that the very act of targeting a particular leader of an enemy force in an armed conflict must violate the laws of war. But individuals who are part of such an armed group are belligerents and, therefore, lawful targets under international law. During World War II, for example, American aviators tracked and shot down the airplane carrying the architect of the Japanese attack on Pearl Harbor, who was also the leader of enemy forces in the Battle of Midway. This was a lawful operation then, and would be if conducted today. Indeed, targeting particular individuals serves to narrow the focus when force is employed and to avoid broader harm to civilians and civilian objects. 
United States, ‘The Obama Administration and International Law’, Speech by the Legal Adviser of the US Department of State, given at the Annual Meeting of the American Society of International Law, Washington DC, 25 March 2010.
[emphasis in original]
The US Air Force Pamphlet (1976) states that the “civilian population as such, as well as individual civilians, shall not be made the object of attack”. 
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(a)(1)(a).
The Pamphlet adds: “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 killing protected civilians”. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 15-3(c)(4).
The US Naval Handbook (1995) states: “Civilians and civilian objects may not be made the object of attack.” 
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), § 8.1.2; see also §§ 11.2 and 11.3.
The Handbook also states that carrying out a “bombardment, the sole purpose of which is to attack and terrorize the civilian population” is an example of a war crime. 
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), § 6.2.5.
The US Manual for Military Commissions (2007), Part IV, Crimes and Elements, includes in the list of crimes triable by military commissions:
ATTACKING CIVILIANS.
a. Text. “Any person subject to this chapter who intentionally engages in an attack upon a civilian population as such, or individual civilians not taking active part in hostilities, shall be punished, if death results to one or more of the victims, by death or such other punishment as a military commission under this chapter may direct, and, if death does not result to any of the victims, by such punishment, other than death, as a military commission under this chapter may direct.”
b. Elements.
(1) The accused engaged in an attack;
(2) The object of the attack was a civilian population as such, or individual civilians not taking direct or active part in hostilities;
(3) The accused intended the civilian population as such, or individual civilians not taking direct or active part in hostilities, to be an object of the attack;
(4) The accused knew or should have known of the factual circumstances that established the civilian status; and
(5) The attack took place in the context of and was associated with armed conflict.
c. Comment. The intent required for this offense precludes its applicability with regard to collateral damage or death, damage, or injury incident to a lawful attack.
d. Maximum punishment. Death, if the death of any person occurs as a result of the attack on civilians. Otherwise, confinement for life. 
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(2), p. IV-4.
The US Naval Handbook (2007) states: “Civilians … may not be made the object of deliberate or indiscriminate attack”. 
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, § 8.3; see also § 5.3.2.
The Handbook also states that examples of war crimes that could be considered as grave breaches of the 1949 Geneva Conventions include carrying out a “bombardment, the sole purpose of which is to attack and terrorize the civilian population”. 
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, § 6.2.6(6).
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements, defines a protected person as follows:
The term “protected person” means any person entitled to protection under one or more of the Geneva Conventions, including—
(A) civilians not taking an active part in hostilities. 
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, § 1(a)(2)(A), p. IV-1.
The manual includes in the list of crimes triable by military commissions:
ATTACKING CIVILIANS.
a. Text. “Any person subject to this chapter who intentionally engages in an attack upon a civilian population as such, or individual civilians not taking active part in hostilities, shall be punished, if death results to one or more of the victims, by death or such other punishment as a military commission under this chapter may direct, and, if death does not result to any of the victims, by such punishment, other than death, as a military commission under this chapter may direct.”
b. Elements.
(1) The accused engaged in an attack;
(2) The object of the attack was a civilian population as such, or individual civilians not taking direct or active part in hostilities;
(3) The accused intended the civilian population as such, or individual civilians not taking direct or active part in hostilities, to be an object of the attack;
(4) The accused knew or should have known of the factual circumstances that established the civilian status; and
(5) The attack took place in the context of and was associated with hostilities.
c. Comment. The intent required for this offense precludes its applicability with regard to collateral damage or death, damage, or injury incident to a lawful attack.
d. Maximum punishment. Death, if the death of any person occurs as a result of the attack on civilians. Otherwise, confinement for life. 
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(2), pp. IV-3 and IV-4.
The US Military Commissions Act (2006), passed by Congress following the US Supreme Court’s decision in Hamdan v. Rumsfeld in 2006, amends Title 10 of the United States Code as follows:
§ 950v. Crimes triable by military commissions
“(a) DEFINITIONS AND CONSTRUCTION. – In this section:
“ …
“(2) PROTECTED PERSON. – The term “protected person” means any person entitled to protection under one or more of the Geneva Conventions, including –
“(A) civilians not taking an active part in hostilities. 
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. 2625, § 950v(a)(2)(A).
The Act further states:
“(b) OFFENSES. – The following offenses shall be triable by military commission under this chapter at any time without limitation:
“ …
“(2) ATTACKING CIVILIANS. – Any person subject to this chapter who intentionally engages in an attack upon a civilian population as such, or individual civilians not taking active part in hostilities, shall be punished, if death results to one or more of the victims, by death or such other punishment as a military commission under this chapter may direct, and, if death does not result to any of the victims, by such punishment, other than death, 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)(2).
The US Military Commissions Act (2009) amends Chapter 47A of Title 10 of the United States Code as follows:
§ 950p. Definitions; construction of certain offenses; common circumstances
“(a) DEFINITIONS.—In this subchapter:
“ …
“(2) The term “protected person” means any person entitled to protection under one or more of the [1949] Geneva Conventions, including civilians not taking an active part in hostilities … 
United States, Military Commissions Act, 2009, § 950p(a)(2).
The Act also states:
§ 950t. Crimes triable by military commission
“The following offenses shall be triable by military commission under this chapter at any time without limitation:
“ …
“(2) ATTACKING CIVILIANS.—Any person subject to this chapter who intentionally engages in an attack upon a civilian population as such, or individual civilians not taking active part in hostilities, shall be punished, if death results to one or more of the victims, by death or such other punishment as a military commission under this chapter may direct, and, if death does not result to any of the victims, by such punishment, other than death, as a military commission under this chapter may direct. 
United States, Military Commissions Act, 2009, § 950t(2).
On 1 September 1939, the US President wrote to the Governments of France, Germany, Italy, Poland and the United Kingdom asking “every government which may be engaged in hostilities publicly to affirm its determination that its armed forces shall in no event, and under no circumstances, undertake the bombardment from the air of civilian populations”. 
United States, Letter from Franklin D. Roosevelt to the governments of France, Germany, Italy, Poland and the United Kingdom, 1 September 1939, reprinted in Eugene M. Emme (ed.), The Impact of Airpower: National Security and World Politics, Van Nostrand, Princeton, 1959, p. 68.
In 1972, the General Counsel of the US Department of Defense considered that the prohibition on launching attacks against the civilian population was a general principle of the law of armed conflict which was declaratory of existing customary international law. 
United States, Letter from J. Fred Buzhardt, General Counsel of the Department of Defense, to Senator Edward Kennedy, Chairman of the Subcommittee on Refugees of the Committee on the Judiciary, 22 September 1972, AJIL, Vol. 67, 1973, pp. 122–124.
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: “The law of war also prohibits attacks on civilians and civilian objects as such. This unchallenged principle is that civilians (and persons hors de combat) whether in occupied territory or elsewhere must not be made the object of attack.” 
United States, Statement of 25 September 1974 at the Conference of Government Experts on Weapons which may Cause Unnecessary Suffering or have Indiscriminate Effects, Lucerne, 24 September–18 October 1974, reprinted in Arthur W. Rovine, Digest of United States Practice in International Law, 1974, Department of State Publication 8809, Washington, D.C., 1975, p. 713.
In 1991, in a diplomatic note to Iraq concerning operations in the Gulf War, the United States stated: “The civilian population, as such, as well as individual civilians, should not be the object of attack.” 
United States, Department of State, Diplomatic Note to Iraq, Washington, 19 January 1991, annexed to Letter dated 21 January 1991 to the President of the UN Security Council, UN Doc. S/22122, 21 January 1991, p. 2.
In another such diplomatic note, the United States reiterated: “the civilian population, as such, is not the object of attack”. 
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, p. 4.
In 1991, in a report submitted to the UN Security Council on operations in the Gulf War, the United States stated: “Over 52,000 coalition air sorties have been carried out since hostilities began on 16 January. These sorties were not flown against any civilian or religious targets or against the Iraqi civilian population.” 
United States, Letter dated 8 February 1991 to the President of the UN Security Council, UN Doc. S/22216, 13 February 1991, p. 1.
In 1992, in its final report to Congress on the conduct of the Gulf War, the US Department of Defense stated: “As a general principle, the law of war prohibits … the direct, intentional attack of civilians not taking part in hostilities”. 
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. 622.
In several reports submitted in 1992 to the UN Security Council pursuant to paragraph 5 of Security Council Resolution 771 (1992) on grave breaches of the 1949 Geneva Convention IV committed in the former Yugoslavia, the United States described “deliberate attacks on non-combatants” perpetrated by the parties to the conflict. 
United States, Former Yugoslavia: Grave Breaches of the Fourth Geneva Convention, annexed to Letter dated 22 September 1992 to the UN Secretary-General, UN Doc. S/24583, 23 September 1992, p. 8; Former Yugoslavia: Grave Breaches of the Fourth Geneva Convention (Third Submission), annexed to Letter dated 5 November to the UN Secretary-General, UN Doc. S/24791, 10 November 1992, p. 19; Former Yugoslavia: Grave Breaches of the Fourth Geneva Convention (Fourth Submission), annexed to Letter dated 7 December 1992 to the UN Secretary-General, UN Doc. S/24918, 8 December 1992, p. 14.
In its written statement submitted to the ICJ in the Nuclear Weapons case in 1995, the United States stated: “The law of armed conflict precludes making civilians the object of attack as such.” 
United States, Written statement submitted to the ICJ, Nuclear Weapons case, 20 June 1995, p. 22.
According to the Report on US Practice: “It is the opinio juris of the United States that it is prohibited to launch attacks against the civilian population as such.” 
Report on US Practice, 1997, Chapter 1.4.