Day fourteen of Israel’s assault on Hamas, and still no sign of a letup. But there were some significant developments: In Gaza, the death toll topped five hundred people, and the United Nations Relief Works Agency for Palestinian Refugees announced that more than a hundred thousand Gaza residents have sought refuge in dozens of the relief shelters that it has opened. In Israel, rockets fired from Gaza continued to explode in civilian areas, and the Israel Defense Forces (I.D.F.) said that twenty-five of its soldiers had been killed since it launched a ground offensive late last week. (Two of them were American citizens.)

Many, if not most, of the victims in Gaza appear to have been civilians. The Gaza Health Ministry said on Tuesday that an Israeli shell hit the third floor of a hospital in the center of the Gaza Strip, killing five people and badly damaging an intensive-care unit. According to some reports, ambulances called in to pick up the wounded and take them to another hospital were fired on by Israeli Defense Forces units. These incidents came after Doctors Without Borders, which has medical teams on the ground, issued a statement saying that “the majority of the dead and wounded in Gaza are civilians and medical workers are also coming under fire.”

In Washington, meanwhile, President Obama finally called for a ceasefire. Once again, though, he stopped well short of criticizing the Israeli government for bombing densely populated urban areas and inflicting so many casualties. In a statement delivered from the White House lawn, which also covered the situation in the Ukraine, he devoted just three paragraphs to Gaza, noting that he had dispatched John Kerry, the Secretary of State, to the Middle East, and had “instructed him to push for an immediate cessation of hostilities based on a return to the November, 2012, ceasefire agreement between Israel and Hamas in Gaza.”

The President reiterated his position that “Israel has a right to defend itself against rocket and tunnel attacks from Hamas,” while saying, again, that “we have serious concerns about the rising number of Palestinian civilian deaths and the loss of Israeli lives.” He went on: “And that is why it now has to be our focus and the focus of the international community to bring about a ceasefire that ends the fighting and that can stop the deaths of innocent civilians, both in Gaza and in Israel.”

In many parts of the world, where the rising casualty list in Gaza is leading the news, the President’s statement will be regarded as a case of closing the stable door well after the horse has bolted. (The White House and State Department ought to have anticipated heavy civilian casualties once Israel launched an attack.)

But a U.S.-led ceasefire initiative could provide the government of Benjamin Netanyahu with a final opportunity to pull its forces out of Gaza before they get bogged down in a lengthy and costly ground war.

Reports from Israel suggest the I.D.F. has been surprised (and even impressed) by the ferocity and effectiveness of the Hamas fighters, and that there is a mounting feeling that, with seven more Israeli soldiers having been killed in the past twenty-four hours, Benjamin Netanyahu’s government will soon be faced with the choice of escalating the military campaign or declaring victory and withdrawing. “In view of the stiff resistance put up by Hamas, the level of destruction, if fighting continues, may reach that of Beirut in 2006,” Amos Harel wrote in Haaretz.

Is Netanyahu prepared for that? Is Israel? Since the Prime Minister of Israel has insisted all along that the aims of Operation Protective Edge are limited—degrading Hamas’s infrastructure and reducing its ability to launch rocket attacks—he seems to have some wiggle room. On Tuesday, the I.D.F. announced that it had already uncovered fourteen tunnels in the Gaza Strip, some of which were twenty-five metres deep and reinforced with concrete. Having destroyed these tunnels and foiled, or so he claims, several terrorist attacks on Israeli communities close to the border, Netanyahu may be able to claim that the military escapade has accomplished its aims, and he may be able to bring it to an end. That, at least, is what Kerry and the embattled residents of Gaza will be hoping for.