It is a casualty rate that would have unimaginable before the start of the Israel-Hamas war. More than 400 Palestinians have been reported killed after 10 hours of resumed Israeli airstrikes on Tuesday, including, according to one early report, at least six members of one family in an attack on a car east of Khan Younis.
Though it is too soon to determine how many noncombatants died in attacks that Israel says were directed at Hamas military commanders and political officials (casualty totals from Gaza’s health ministry do not distinguish combatants from the uninvolved), the likelihood is that civilians will have been killed in large numbers.
More than 7,000 incidents in which civilians were killed were recorded by the monitoring group Airwars during the previous 15-month war, a conflict in which the bombing has been so intense it has raised questions about the military doctrine of proportionality that is supposed to reduce the impact of warfare on noncombatants.
“Our analysis shows the number of casualties is far beyond anything we have seen from comparative air campaigns in the last decade,” says Emily Tripp, the director of Airwars, which has monitored the impact of bombing campaigns in wars for more than 10 years.
International humanitarian law, underpinned by the Geneva conventions, is intended to act as a check on armed conflict. Parties in war are expected to adhere to the principle of distinction between militaries and civilians, and the principle of proportionality. Attacks against military objectives which cause excessive civilian casualties relative to the advantage gained are, in theory, a war crime.
Hamas showed no respect for distinction or proportionality in the 7 October attack in which about 1,200 were killed. Six months after, Israel’s social security agency said 814 civilian casualties had been killed, 39 of them children, in brutal attacks on the Nova music festival, where an estimated 365 people were killed, and at Nahal Oz and other kibbutzim near the Gaza Strip.
Israel’s military response has been ferocious, leading to the deaths in Gaza of more than 49,000 people – civilians and military personnel – about 59% of whom were women, children or elderly, according to Palestinian health authorities. These figures are so high they raise questions of their own.
“Even without looking at specific incidents, it becomes hard to see how harm may have been mitigated towards civilians and how the principles of distinction and proportionality were applied,” said Anna Gallina, a specialist international humanitarian lawyer with Global Rights Compliance.
In some incidents, the number of civilian casualties is extraordinary. At least 126 Palestinians are recorded to have been killed in the bombing of the densely populated Jabalia refugee camp on 31 October 2023. The target, in an attack that took place with no warning, was Hamas’s northern commander, Ibrahim Biari, and an underground base, Israel’s military said. Craters 40ft deep were left behind.

There is also ample evidence to suggest the Israeli military relaxed its own rules of engagement. Reports in Israeli publication +972 magazine and the Guardian, citing sources within the IDF, said it was deemed permissible to kill up to 15 to 20 civilians when attacking a person identified as a junior Hamas operative and 100 for a commander.
On 25 October 2023, the IDF struck a block above what it said was a “Hamas terror tunnel” multiple times. The attack destroyed the al-Taj residential building, and 101 people (44 children, 37 women, 26 men) were counted by Airwars as killed.
When Israel dramatically increased its air campaign against Hezbollah in Lebanon last September after nearly a year of tit-for-tat cross-border strikes, 492 civilians and military were reported by Beirut as killed in a single day. A few days later 73 were killed when a six-storey apartment block was destroyed by Israeli missiles in the village of Ain el-Delb. Six victims were identified as having links to Hezbollah.
Craig Jones, the author of a study of military lawyers, said that while Nato militaries, in the US under the former president Joe Biden, and particularly in Europe, have become increasingly cautious about the risks of civilian casualties, “Israel has gone 180 degrees in the opposite direction” during the Gaza war.
Britain, by contrast, is particularly cautious. The UK military says it operates a policy of no civilian casualties. Though the RAF’s claim that its bombing raids have only caused one civilian death during the war against Islamic State has been repeatedly challenged, former insiders say the commitment to avoid civilian harm was genuine.
“If it was thought there would be any civilian casualties then the strike would be aborted even if the aircraft was already in the air,” said a former UK government lawyer. “The Israelis have always been absolutely wildly different to us and this is discussed openly.”
Israel’s argument is that it is fighting a different kind of war. Hamas, Israel has repeatedly argued, deliberately erased civilian-military distinctions throughout the conflict. It accuses the Palestinian group of locating command centres in tunnel networks below buildings such as hospitals in Gaza’s dense urban environment, while its besieged 2.3 million citizens had nowhere to escape.
A former IDF military lawyer, who asked not to be named, asked how the British would act if the UK was invaded. “This was a war we thought we could lose – and when you are under direct attack, it was very important to get rid of the main commanders of Hamas.” Because the threat was considered existential, it justified an alternative approach, the former lawyer added.
Key western allies – the UK and US – have not concluded that Israel has violated the doctrine of proportionality. A letter from David Lammy, the UK foreign secretary, to the foreign affairs committee from January said it had “not been possible to make an assessment of Israel’s compliance with the principle of proportionality” because of “the opaque and contested information environment in Gaza”.

Last May, a leaked US state department review requested by Biden on whether countries receiving US arms were using them “in accordance with international humanitarian law” concluded that a determination was not possible because “Israel has not shared complete information” about its decision-making processes.
“What we have seen is that there’s been no accountability for this gross widening of the whole concept of proportionality,” said Dearbhla Minogue, a human rights lawyer with Global Legal Action Network. “You could imagine it loosening other militaries’ standards in future conflicts.”
Donald Trump’s administration, which says it was consulted before Israel’s overnight assault, has made clear it is strongly pro-Israel. At the same time, the US is rewriting its own rules. Earlier this month, Pete Hegseth, the defense secretary, moved to cut positions of those who work to mitigate and assess risks to civilians – and began an overhaul of US military lawyers aimed at loosening the rules of engagement.
On Saturday, the US military bombed the Houthis in Yemen, killing 53 and wounding 98 according to the Houthi health ministry, including women and children. By contrast, five were reported killed and six injured in joint US-UK air raids on the Houthis in mid-January 2024. Early indications are that the US doctrine is already changing in practice.