The Israel Defense Forces insist that Operation Defensive Pillar is taking pains to minimize civilian casualties by "cleaning the target" before a strike. The fatalities may be low compared with the previous Gaza conflict, but Sunday in the coastal strip was still bloody

ALESSIO ROMENZI for TIME Palestinians shout at the Al Shifa Hospital morgue after the arrival of the body of Ramez Harb, an Islamic Jihad militant killed by an Israeli airstrike on the Shuruq building in Gaza City, Nov. 19, 2012.

On the day they buried Ahmed Jabari, the Hamas commander blown apart in what Israel calls a “targeted killing,” a man named Jihad Misharawi cradled the corpse of his 11-month-old son, killed when an apparently errant Israeli shell pierced the roof of their Gaza home. The father’s grief was captured in a compelling Associated Press photograph that Misharawi might have appreciated in his professional capacity: he works for the BBC as a photo editor, the job that involves deciding what images to send out to the world when the story becomes the death of civilians, as it is becoming in Gaza.

Until Sunday, the number of Palestinian bystanders killed in the Israeli assault on the crowded, poverty-stricken stretch of sand may have been as low as 16, barely half the number of fatalities among militants across the first four days. That proportion, if it had stood, would have been exceptional for any war — some researchers say civilians historically account for 80% of war deaths — but especially for the Israel Defense Forces (IDF) doing battle in the Gaza Strip. The last time the IDF went into Gaza, four years ago, 1,400 Palestinians were killed, at least half of them civilians. Israel emerged from its victory facing a torrent of international approbation and a U.N. inquiry alleging war crimes.

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The Jewish state was not keen to repeat the experience. The rhetoric coming out of Israel can be incendiary: Monday’s Jerusalem Post contained an op-ed by Gilad Sharon, the youngest son of former Prime Minister Ariel Sharon, arguing, “We need to flatten entire neighborhoods in Gaza. Flatten all of Gaza. The Americans didn’t stop with Hiroshima — the Japanese weren’t surrendering fast enough, so they hit Nagasaki too.” Earlier, Interior Minister Eli Yishai declared that the goal of the current operation is to “send Gaza back to the Middle Ages.” But Israel’s most senior officials appear keen to maintain the approval of Western governments, both by emphasizing that Gaza militants provoked the assault by firing hundreds of missiles toward Israeli communities and by arguing their answering offensive — more than 1,350 air, tank and warship strikes so far — is both fierce and restrained. The public relations section of the IDF is proactive on the question of minimizing civilian deaths, posting videos from earlier operations showing the trouble Israeli pilots take to avoid injuring bystanders while pursuing military targets. Several show gunsight footage of pilots diverting their bombs — after release, in flight — when the car they are aiming at enters a garage, or pulls up beside a cluster of pedestrians. The missiles explode a safe distance away.

“We are learning, and we are improving from last time,” a senior Israeli officer told TIME late last week. “But eventually we will make a mistake, and there’ll be an accident. There’ll be a picture of children who have been hit, and it will be devastating for us.”

That’s what happened on Sunday. An Israeli air strike leveled a house in Gaza City, and among the 10 people killed were four children and four women. The home apparently belonged to a militant, and an Israeli official said the occupants had received a telephone call warning them that the house was going to be bombed. “Apparently they didn’t leave,” the official said.

Such warning calls — which Palestinians describe in a video the IDF compiled — are among the precautions Israeli forces say are intended to minimize loss of life and also forestall a repeat of the torrent of criticism that Israel faced four years ago, in Operation Cast Lead. In the command center during that campaign, according to a military source, a policy that reflexively directed fire to the location from which a rocket had just been launched surely raised the number of civilian casualties. Israeli commanders are not doing that in the current operation.

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In Operation Defensive Pillar, as the ongoing assault is officially known, specific efforts are made to avoid hitting bystanders, Israeli officials maintain. When approaching a target where civilians are believed to be, Israeli pilots will make a first pass to drop a sound bomb (or feeble live charge) near the target, intending to scare people away. Commanders refer to this as “cleaning the target.” The aircraft then returns to deliver live munition meant to destroy the missile launcher, weapons cache or — lately — home. Since Wednesday, Israeli forces have destroyed at least 14 Gaza residences belonging to a Hamas minister or commander. Again, Israeli officials say care is taken to limit damage to surrounding structures and bystanders, using a penetrating munition that detonates deep inside the structure, causing it to collapse inward.

Any contrast with Cast Lead is intentional. That operation began with a massive attack on a police graduation, cutting down dozens of cadets standing in formation. From the start, Prime Minister Benjamin Netanyahu framed Defensive Pillar as a series of “surgical strikes,” and five days later, the relatively refined approach may be having an effect. Though Israel has called up 40,000 reserves in preparation for a possible ground assault, attention shifted over the weekend to the terms of a possible cease-fire, mediated by Egypt, that would avoid a ground war neither side seems to want. Officials say Israel’s primary demand is a total cessation of rocket fire into its territory (900 of which have been fired since Wednesday, resulting in three Israeli deaths). For Hamas, the primary demand is for a promise that Israel will stop killing its senior officials and commanders.

The sheer number of Israeli air strikes challenges the effort to confine the damage to military targets. Between dusk on Sunday and dawn on Monday, another 150 massive explosions echoed across the densely packed enclave, as Israeli warships joined warplanes in pounding Hamas police stations located throughout Gaza. Each strike involves complex coordination among several agencies — typically including Israel’s internal security agency, Shin Bet, which runs informants in Gaza, military intelligence and the Israeli air force. The potential for something to go amiss rises with each outing. “Statistical probabilities are working against us,” the Israeli officer tells TIME.

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By Sunday night, the independent Palestinian news service Maan had tallied 72 Palestinian deaths in Gaza, including 24 on Sunday alone. The U.N.’s Office for the Coordination of Humanitarian Affairs, using figures from a few hours earlier, counted 53 fatalities, including 29 civilians, 11 of them children. Those killed on Sunday included an 18-month-old boy named Eyad in the al-Bureij refugee camp, 9-year-old Tasneem Nahhal in the al-Shati camp and Jumana Abu Asaifan, age 1.

“You talk about surgical strikes,” the Guardian’s Harriet Sherwood said to a senior Israeli official at a news conference in Jerusalem on Sunday afternoon. “I’ve actually just come here straight from Gaza, and the idea that the strikes are surgical is, um, not quite accurate. And actually the casualty toll has increased quite a lot in the last 24 hours. A lot of them are civilians. A lot of children are now being killed.”

The Israeli official was Moshe “Bogi” Ya’alon, whose titles include deputy prime minister and Minster for Strategic Affairs. In the 1990s, he was Chief of Staff of the IDF. He stood by “surgical.” “It is within our values as well as our interest to avoid what is called collateral damage, or hitting noninvolved people,” Ya’alon said. “For our soldiers, hitting noninvolved people — I’m talking about women and kids — is a failure. Not like it is in the other side. They target deliberately our civilians. But when they use their own civilians as human shields, what is our choice? To allow them to hit our civilians?”

— With reporting by Aaron J. Klein / Tel Aviv

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