Before World War II . Shells for the 42 cm guns were generally 1.5 m long and weighed between 400 and 1,160 kg. The reasons behind the prohibition of indiscriminate attacks were already spelled out by one of the founders of international law,
Francisco de Vitoria. A passage of his "Second Relectio on the Indians, or on the Law of War" (1532) can be read as an anticipation of the modern principle of
proportionality: The first attempt at codifying a general prohibition of indiscriminate attacks were the 1923 Hague Rules of Air Warfare, which never came into force. They were drafted under the impression of
World War I, where recourse to
aerial bombing of cities had first become widespread.
Strategic bombing by German forces using airships (such as the
Zeppelin raids over England and during the
siege of Antwerp) and long-range artillery (the "
Big Bertha" cannon) raised the issue of how to contain indiscriminate military attacks. The Hague Rules proposed that in cases where the military targets "are so situated, that they cannot be bombarded without the indiscriminate bombardment of the civilian population, the aircraft must abstain from bombardment." While supported by United States and Japan, the Hague Rules were rejected by France and the United Kingdom. At the 1932 World Disarmament Conference, the
British government argued that limitations to aerial warfare should not apply to
colonies: as former Prime Minister
David Lloyd George declared, "we insisted on reserving the right to bomb niggers". shows a burned and terrified baby following an aerial attack on 28 August 1937 during the
Battle of Shanghai. Before
World War II, the deadliest indiscriminate attacks occurred outside Europe, in the
Italian invasion of Ethiopia (1935-1936) and in the
Japanese invasion of Manchuria (1931-1932) and
China (1937-1945). However, it was only with the
Spanish Civil War (1936-1939), as consequence of the
bombing of Madrid,
Guernica and other cities, that indiscriminate bombing of civilian populations first came to the attention of Western audiences. Notwithstanding the efforts by the
ICRC and the drafting of the 1938 Convention for the Protection of Civilian Populations Against New Engines of War, which never became legally binding, World War II broke out in the absence of an international regime prohibiting indiscriminate attacks. The basic provision limiting aerial warfare was set forth in the 1907 Fourth Hague Convention, and forbade any bombardment of undefended towns, but allowed bombardment of defended towns, or towns that were under attack on the ground. According to international law of the time, "indiscriminate bombing of a defended city or a defended area [was] permissible", as the
District Court of Tokyo exposed in
Ryuichi Shimoda v. The State (1963). As British Prime Minister
Neville Chamberlain stated to the
House of Commons of the United Kingdom in June 1938: there was "no international code of law with respect to aerial warfare which is the subject of general agreement."
World War II and aftermath in March 1945 was the single deadliest air raid of World War II leaving an estimated 100,000 civilians dead and over one million homeless. At the onset of the war, U.S. President
Franklin D. Roosevelt attempted to mitigate this situation by launching an
Appeal to the Belligerents to Refrain from the Bombing of Open Towns. The appeal was accepted by the German, French and British governments and proved to be quite effective in practice, as during World War II it remained an option to declare a city "
open", abandon all defensive efforts and avoid bombing, as happened in Paris, Brussels, Rome, Athens and elsewhere. The vast majority of cities were defended and subjected to heavy fire during the war;
Heinrich Himmler declared that "No German city will be declared an open city" and hundreds of thousands of civilians died as consequence of massive bombing during the six years of the conflict. From the start, Allied policy was conditioned upon Axis observance of the
norm of reciprocity. "
Reprisals" could lawfully follow any belligerent's bombardment of civilians, which was the legal ramification of the norm of reciprocity", and with the indiscriminate attacks by German forces against Polish targets during the
invasion of Poland that began in September 1939 the norm of reciprocity "was the only guarantor of a fighting chance at survival in the face of an enemy who disregarded important humanitarian principles". Both the
Allied and
Axis powers carried out
carpet bombings during the war, such as the attacks on
Wieluń,
Rotterdam,
Warsaw,
London,
Coventry and on
Shanghai and
Chongqing, on the one side, and the attacks on
Cologne,
Berlin,
Hamburg,
Dresden and on several
Japanese cities including
Tokyo, on the other. Under current international humanitarian law, most of these bombings would probably qualify as deliberate
attacks on civilians rather than as indiscriminate attacks, as they were conducted with the explicit intention of targeting "morale". In the last 12 months of the war, Germany introduced the paradigmatic case of indiscriminate weapon: the so-called "flying bombs" or "
V-weapons" (
V-1 flying bomb,
V-2 rockets and
V-3 cannon). These long-range ballistic missiles could not be directed at a specific military objective but were pointed in the general direction of large metropolitan areas; they "could hardly hit a particular city, let alone a specific point within them". Equally indiscriminate but less effective were the Japanese
Fu-Go incendiary balloons – the first intercontinental weapon. The deadliest indiscriminate weapons used during World War II were by far the
atomic bombs detonated by the United States over
Hiroshima and Nagasaki. After the war, the German and Japanese leaderships were not pursued for deliberate and indiscriminate air attacks on the civilian populations. Their bombing campaigns had arguably been paralleled or surpassed by those carried out by the Allies, and in the
Nuremberg and
Tokyo indictments no attempt was made to frame indiscriminate attacks as war crimes. During the negotiations of the 1949
Geneva Conventions, protection of civilians was a controversial subject, and the British representatives opposed any restriction to the freedom to carry out bombing – at the time, both France and the United Kingdom were engaged in "
aerial policing" as part of
counterinsurgency efforts in their colonial empires. As a result, the conventions left out the guidelines for the protection of civilians from the effect of hostilities in international conflicts while
Common Article 3 provides protection
only to the moment the person is under the physical control of a party to a non-international conflict. Between 1945 and 1977, Western nations carried out intensive bombing campaigns as part of counterinsurgencies in the
Global South. These included France in Madagascar during the
Malagasy Uprising and Algeria during the
Algerian War, the United Kingdom in Malaya during the
Malayan Emergency and Kenya during the
Mau Mau rebellion and the United States in Korea during the
Korean War and Vietnam during the
Vietnam War.
The 1977 Additional Protocols to the Geneva Conventions Additional Protocol I A general prohibition of indiscriminate attack in international conflicts was established in the 1977
Additional Protocol I: • Article 51(4): Indiscriminate attacks are prohibited. Indiscriminate attacks are: • (a) Those which are not directed at a specific
military objective; • (b) Those which employ a method or means of combat which cannot be directed at a specific military objective; • (c) Those which employ a method or means of combat [that] strike military objectives and civilians or civilian objects without
distinction. • Article 51(5): Among others, the following types of attacks are to be considered as indiscriminate: • (a) An attack by
bombardment by any methods or means which treats as a single military objective a number of clearly separated and distinct military objectives; … and • (b) An attack which may be expected to cause incidental loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof, which would be excessive in relation to the concrete and direct military advantage anticipated. During the diplomatic conference for the drafting of Additional Protocol I, the possibility was referred to of distinguishing the rules applicable to the aggressor from the rules applicable to the victim of the aggression, but several delegations opposed the proposal, which was eventually rejected by the conference. The diplomatic conference attached great importance to the prohibitions of deliberate and indiscriminate attacks on civilians set forth in Article 51, as is shown by the fact that Article 51 is one of the provisions to which no
reservations can be made, and by the fact that its violation is qualified as a "grave breach" amounting to a
war crime under Article 85. As of 2022, Additional Protocol I has been ratified by 174 states, with the notable exceptions of India, Iran, Israel, Pakistan, Thailand and the United States. However, the practice of indiscriminate attack in international conflicts continued during the
Indonesian occupation of East Timor (1975-1999) and the
Palestinian rocket attacks on Israel as part of the
Arab–Israeli conflict. Indiscriminate attacks, and occasionally also deliberate attacks on
civilians, were particularly deadly during the
Soviet-Afghanistan war, in the "
war of the cities" (1984-1988) during the
Iran-Iraq war, and in the
first Nagorno-Karabakh war between Armenia and Azerbaijan.
Additional Protocol II Unlike Additional Protocol I, there is no explicit provision in
Additional Protocol II spelling out the distinction between civilians and combatants during hostilities nor prohibiting indiscriminate attacks in non-international conflicts. However, Article 13 of Protocol II does state that civilians are entitled to protection "against the dangers arising from military operations", which is construed as indirectly banning indiscriminate attacks. As of November 2023, Additional Protocol II had been ratified by 169 countries, with the
United States,
India,
Pakistan,
Turkey,
Iran,
Iraq,
Syria, and
Israel being notable exceptions. However, the United States, Iran, and Pakistan signed it on 12 December 1977, which signifies an intention to work towards ratifying it. The Iranian signature was given prior to the
1979 Iranian Revolution. In the 1980s and 1990s, indiscriminate attacks were recorded in non-international conflicts in the
bombing of Lebanon in July 1981 and the
siege of Beirut in 1982 during the
Lebanese Civil War,
Salvadoran Civil War (1979-1992),
battle of Kabul during the
Afghan Civil War (1992–1996), and in the
first and
second Chechen war, with the devastating
sieges of Grozny in 1994-1995 and
1999-2000.
From the Gulf War onwards The 1991
Gulf War and the
wars of the former Yugoslavia, including
Kosovo, have been regarded as the first attempts to avoid indiscriminate damage in the operations of war; the use of
smart bombs was instrumental to that end. Although bombings during the Gulf War destroyed critical infrastructures in Iraq leading to thousands of
civilian deaths, the war was widely celebrated for the "most discriminate air campaign in history", with relatively few Iraqi civilians (around 3,000) directly killed by the bombings. At the time of the Gulf War, many legal scholars doubted that Additional Protocol I codified customary international humanitarian law and was therefore binding upon the United States, which had not signed the convention.
Human Rights Watch published a report arguing that "many of the Protocol’s provisions", including the prohibition of disproportionate and other indiscriminate attacks, "reaffirm, clarify or otherwise codify pre-existing customary law restraints on methods and means of combat and, thus, are binding on all nations regardless of ratification". The
2009 Gaza war marked by indiscriminate
use of rockets by the Palestinians and by indiscriminate airstrikes from the Israeli Defence Forces, as documented in the UN
Goldstone report. Indiscriminate attacks have been documented in the
Syrian civil war by foreign soldiers from Russia and Turkey. Syrian government forces have also been accused of carrying out indiscriminate attacks in
Idlib,
Aleppo and other areas. Human rights groups have claimed that the
Syrian Armed Forces are responsible for a systematic campaign of indiscriminate attacks in cities all across the country. During the
2022 Russian invasion of Ukraine, Russia has repeatedly carried out indiscriminate attacks in densely populated areas. In the context of the
Gaza war,
Amnesty International has documented indiscriminate attacks by the Israeli forces on Gaza, which it says have caused mass
civilian casualties and should be investigated as
war crimes. A group of independent United Nations experts also stated that Israel had resorted to indiscriminate attacks against the Palestinian population of Gaza. The United States
2025 airstrike on a migrant detention centre in Saada, Yemen "amounted to an indiscriminate attack" according to Amnesty International. ==Notes==