The divisions in the Jewish community over the war in Gaza broke into the open this week as the number of Israeli soldiers killed reached 27 by Tuesday night and the number of Palestinian deaths neared 600.

And as those fault lines were laid bare, it touched off a debate over the nature of “proportionality” in wartime.

As a wide swath of the Jewish community rallied behind Israel in its bid to take out Hamas’ tunnels, and as polls showed that Americans were solidly backing Israel in its ground incursion, groups on the Jewish left were expressing concern over the mounting Palestinian civilian deaths.

Partners for Progressive Israel (formerly Meretz-USA) late last week urged the international community to “push for an immediate cease-fire” in the Israel-Hamas fighting, and even pressed Israel to “unilaterally” suspend its military actions against Gaza. “The situation,” in which the casualties suffered among Palestinians greatly outnumber those of Israelis, “has become more dire,” stated a press release issued by the group.

J Street, the Washington-based “pro-Israel, pro-peace” organization, posted a blog that “categorically oppose[s] calls for the reoccupation of the Gaza Strip as the goal of [Israel’s current] operation” and expressed “concern” about “the mounting civilian death toll” in Israel.

The group also pulled out of a community rally in support of Israel this week because the roster of speakers, organized by the city’s Jewish Community Relations Council, “did not include a pro-Israel, pro-peace perspective” and that “there was no voice for our concerns about the loss of human life on both sides.”

As the civilian casualties in Gaza have mounted, the issue of proportionality has increasingly entered the public discussion. In England, Deputy Prime Minister Nick Clegg said the “Israeli response” to years of Hamas rocket fire from Hamas “appears to be deliberately disproportionate.”

The questions being asked in the media and in parts of the Jewish community: Is Israel “over-reacting” to Gaza-based attacks? Do one-sided casualty figures strengthen the David vs. Goliath imagery that has dominated part of the Middle East debate for years, with Palestinians pictured as a beleaguered underdog? Does the Iron Dome anti-missile defense system give Israel, as some critics of the Jewish state have alleged, an “unfair advantage?”

Some of these questions surfaced in the Gaza wars in 2009 and 2012, but they seem especially pointed this time around in the wake of Secretary of State John Kerry’s quip characterizing Israel’s Gaza mission as “a hell of a pinpoint operation.” In response to such concerns, Shoshana Bryen, senior policy director of the Jewish Policy Center, this week issued a position paper on “The Doctrine of Proportionality” that cited scholarly opinions of what proportionality in warfare means.

“Proportionality in international law is not about the equality of death or civilian suffering, or even about [equality of] firepower,” she quoted Luis Moreno-Ocampo, chief prosecutor of the International Criminal Court, as writing. “Proportionality weighs the necessity of a military action against suffering that the action might cause to enemy civilians in the vicinity.”

“Civilian casualties are much to be mourned, but what becomes clear — absent the propaganda element or a shaky notion of sportsmanship — is that Israel has the right and indeed the obligation to defend its people, has the right to ‘win’ the war of self-defense that it is fighting, and has taken account of the requirements of international law regarding ‘proportionality’ and ‘military necessity,’” Bryen wrote.

“The word [disproportionate] surfaces a lot,” said David Harris, executive director of the American Jewish Committee. “What would be a proportionate response to the thousands of missiles that have been fired at Israel in this year alone? Does [proportionate] mean that unless Israel suffers the same number of casualties as the Palestinians in Gaza, that [Israel’s military response] is wrong?”

Sympathy for people who are perceived as underdogs is inevitable, said Ephraim Sneh, former Knesset member and deputy minister of defense, in a conference Tuesday afternoon sponsored by the Israel Policy Forum and the JCC in Manhattan. “In a confrontation between a tank and an ambulance, the ambulance will win,” said Sneh, who now serves as chairman of S. Daniel Abraham Center for Strategic Dialogue at Netanya Academic College. In other words, a humanitarian cause will trump strength in the eyes of many observers.

“We have bad PR,” he said, adding that Israel has not adequately stressed the steps its soldiers take to avoid civilian casualties.

“We are the strongest military force between the Caspian Sea and Casablanca,” Sneh said. “We shall take advantage of all our technological advantage. It is a high price to pay.” In other words, Israel is able to inflict a large number of casualties in a confrontation.

Several of the Jewish critics of the IDF’s actions in Gaza have cited “disproportionality” as a reason.

Nathan Hersh, managing director of Partners for Progressive Israel, said his organization called on Israel to suspend its war on Hamas because “nothing can happen as long as people are dying. Force alone is not going to stop this conflict.”

But, said some Jewish spokesmen, the Jewish groups that have openly criticized Israeli actions in recent weeks are in a distinct minority.

“Their decibel level is much higher than their numerical [membership] level,” Harris said.

Americans for Peace Now, calling itself “horrified by the spiraling death-toll of the war,” “welcome[d] the Obama administration’s efforts to achieve an immediate cease-fire.” It called “continued fighting in … densely-populated [Gaza] a recipe for more bloodbaths such as the one we witnessed Sunday in Shuja’iyyah, a neighborhood East of Gaza City.”

And a dozen activists from the Jewish Voice for Peace and Jews Say No! organized a street-side rally Tuesday on Broadway outside the office building where American Friends of the IDF is based. Some participants carried signs that stated “No war in Palestine. Not in our name,” and others lay on the ground, covered by shroud-like sheets, impersonating Palestinian Arabs killed by the Israeli army. (JTA reported that nine of the protesters were arrested.)

Despite daily images in the media of Palestinian funerals and damaged homes in Gaza, Israel has retained the backing of American politicians and the U.S. public — both the Senate and the House of Representatives unanimously passed non-binding resolutions that support Israel’s right to defend itself and a CNN poll found that 57 percent of Americans call Israeli actions against Hamas “justified.” (See story on page 14.)

Even comedian Bill Maher, on the HBO Real Time program, listed what he called “8 Rock Solid Points in Defense of Israel,” including, “The Palestinians do not have the moral high ground.”

“I think there is remarkable unity” behind Israel, said Malcolm Hoenlein, executive vice chairman of the Conference of Presidents of Major American Jewish Organizations. He spoke of a “marginalization of those groups who have been critical of Israel and cannot find it in their hearts, even at this time, to express unreserved solidarity.”

Most Jewish organizations have issued recent statements of support for Israel. The Anti-Defamation League: “No government in the world would allows its citizens to be subjected to constant rocket attacks.” The American Jewish Committee: “Israelis of all ages are in an absolutely intolerable situation, with only 15 seconds to reach a shelter for safety and security from the ceaseless, indiscriminate, round-the-clock Hamas attacks.” The National Jewish Democratic Council and the Republican Jewish Coalition issued similar supportive statements.

But Thane Rosenbaum, novelist and director of the Forum on Law, Culture & Society at the NYU Law School, said he is not surprised that Jewish critics of Israel, largely from politically left-wing, intellectual backgrounds, have strengthened their criticism during Israel’s current fighting.

“It is the way of the intellectual that the idea is more important than anything else,” he said. In this case, that idea is “an asymmetrical bargaining position … in the conflict between the Israelis and the Palestinians” that leaves Palestinians in a weaker position. Rosenbaum called this “community of Jewish intellectuals … fully invested in being critical of Israeli policies. I would expect them to double down” in their criticism of Israel.

“I would be very surprised,” he added, “that any intellectual in the far left camp would look at the last three weeks [of daily Hamas rocket attacks] and say, ‘This is my time to support Israel.’”

steve@jewishweek.org