Just over a week before Israel holds elections to choose a new government, the outcome of the war in the Gaza Strip has emerged as a central issue in the campaign, with the candidates sparring over whether the massive military operation went far enough.

The argument reflects the reality that elections here often turn on a single question: Who looks tougher on national security?

The war, initiated to stop Hamas rocket fire that has persisted for years, was viewed by many here as motivated at least in part by electoral politics. Two of the three Israeli architects of the war, Defense Minister Ehud Barak and Foreign Minister Tzipi Livni, are candidates to become the nation's next prime minister.

The operation in Gaza drew condemnation abroad for the high Palestinian death toll, and praise at home for the relatively low number of Israelis killed. But it has not done much to elevate Barak's or Livni's prospects of winning the top job. Now their even-more-hawkish opposition is on the offensive.

In recent days, former prime minister Binyamin Netanyahu, who according to polls appears poised to reclaim his old job, has argued in speeches and interviews that his political rivals ended the war prematurely. Israel, he says, should have destroyed Hamas -- which he views as an outpost of Iranian power on Israel's southern border -- rather than withdrawing amid a shaky cease-fire. He has left little doubt over what he would do if elected.

"The next government will have no choice but to finish the work and remove the Iranian terror base for good," he said in a radio interview last week.

One of his top lieutenants in the right-wing Likud party, Zeev "Benny" Begin, was even more emphatic at a rally in Jerusalem, describing the military operation in Gaza as a failure. "One million Israelis remain under the threat of rockets," Begin, son of Israel's first Likud prime minister, Menachem Begin, told a cheering crowd. "After this operation, the terrorists came out of their hiding places waving not white flags but the green flags of Hamas."

In Israel's fractious political culture, left and right are generally determined by a party's relative willingness to cede land to the Palestinians in exchange for a peace deal, as well as by its criteria for going to war.

Netanyahu's Likud has generally been critical of U.S.-backed negotiations between Israel and the West Bank-based Palestinian Authority, which are aimed at creating a Palestinian state. Netanyahu has also advocated an uncompromising stand against Iran, particularly when it comes to that country's nuclear ambitions. But during his tenure as prime minister in the late 1990s, he demonstrated a willingness to govern more pragmatically than he had campaigned, agreeing to a limited peace accord with the Palestinians on control of the West Bank city of Hebron.

Likud's criticism of the recent Gaza operation is aimed squarely at Netanyahu's two main rivals for the prime ministership, Livni and Barak. They have strongly defended the conduct of the military campaign, while also hinting that Israel is not finished in Gaza and that there could be more attacks before the Feb. 10 elections.

"We are on the right course to achieve peace and quiet," Barak, leader of the center-left Labor Party, told students in the seaside city of Herzliyya. "The operation had real accomplishments. Our deterrence has been restored. Hamas was dealt a blow like no other since its creation."

But he also vowed that Israel would "keep one hand on the pistol."

Beginning Dec. 27 with a surprise air assault, Israeli jets pounded Gaza for 22 days and nights, with tanks overrunning large swaths of the coastal territory.

Approximately 1,300 Palestinians died in the operation, about half of them civilians, according to Gazan medical officials. Thirteen Israelis were killed, three of them civilians.

Israeli Prime Minister Ehud Olmert said in launching the war that the intent was to stop the persistent rocket fire from Gaza into southern Israel and to end the smuggling of weapons into Gaza from Egypt.

But when the dust cleared, Hamas declared victory and quickly reasserted its control over the strip. In the two weeks since the cease-fire took effect, the smuggling has resumed, scattered rocket fire has continued and an Israeli soldier was killed last week in an attack carried out by a radical splinter group of Hamas that does not support the cease-fire. Hamas itself denied involvement but praised the killing.

On Sunday, Palestinian fighters launched about a dozen rockets and mortar shells toward Israel, slightly injuring at least three people, according to the Israel Defense Forces. Olmert, in his weekly cabinet meeting, vowed that Israel's response to the attacks would be "disproportionate." Since the cease-fire took hold, Israel has responded to attacks from Gaza with periodic airstrikes aimed at Hamas fighters and at tunnels.

Although Israel won the war by almost any military standard, Hamas's resilience has provided a political opening for Netanyahu. For more than a year before the government launched the operation, he had agitated for war from his seat as leader of the opposition. During the operation, he was a vocal supporter.

But since it ended, he and his party have gone into attack mode, accusing the government of weakness for not killing top Hamas leaders or reclaiming the strategically important Philadelphi corridor, which runs along the Gazan-Egyptian border and is dotted with smugglers' tunnels. Netanyahu and his allies have tried to paint the decision to halt the operation as just another failure of the ruling Kadima party, which also spearheaded Israel's disengagement from Gaza in 2005.

The argument seems to be working: Netanyahu has consolidated his position as the election's front-runner in recent weeks, despite his opponents' orchestration of a popular war.

"If Likud was in power, the operation would not have ended. It started well, but it ended too soon," said Leon Amoyal, a 59-year-old retiree who traveled to Jerusalem from the northern city of Haifa this week to cheer Netanyahu. "We could have eradicated Hamas."

Netanyahu got a boost last week when one of the operation's key commanders, reserve Brig. Gen. Zvika Fogel, publicly declared that Israel had missed "a historic opportunity" to crush Hamas's military capabilities.

"Hamas was really at a breaking point," said Fogel, who commanded artillery and other units. "We should have turned up the pressure."

Instead, he said, Israel's political leaders first stalled the operation, then pulled the plug, announcing a unilateral cease-fire Jan. 17. Fogel said he believed the decision was made to avoid heavy Israeli casualties in the weeks before an election and to spare President Obama from having to deal with the war during his first days in office. "On January 20th, they didn't want to see the TV screen divided in two parts -- one for the ceremony and the other for the war," he said.

But backers of Livni and Barak say the war ended at just the right moment. In 22 days of fighting, they say, Israel achieved its goals without being drawn into a quagmire. Throughout the war, military planners worried that Israel would sustain high casualty rates if it sent large numbers of ground forces into Gaza's densely packed cities and refugee camps in search of Hamas leaders. They also fretted over what would come next if they really did destroy Hamas: The relatively moderate Fatah movement has little organized presence in Gaza, and a power vacuum in the strip could lead to an even more dangerous situation for Israel.

At a question-and-answer session with students at the Hebrew University of Jerusalem last week, Livni cited her own diplomatic efforts as crucial, first to keeping the war going despite international pressure for it to end, and then to bringing about a responsible conclusion.

Netanyahu, she said, is "an extreme ideologist" who may know how to fight but won't know how to work with allies, including the United States, to achieve peace.

Livni, wary of looking soft, also spoke out forcefully against Hamas and said Israel will continue to strike at the group when necessary. Her party, Kadima, has featured images of tanks rolling into Gaza in its advertisements, part of a bid to toughen her image.

Livni, who took control of the centrist Kadima last year after Olmert stepped aside amid corruption charges, is running second in the polls, with Labor's Barak a distant third.

During the Gaza war, all of the first-tier parties, as well as many of those in the second tier, favored the decision to fight. Even a party considered to be a stalwart of Israel's peace camp, Meretz, initially backed the war, although it later called for a cease-fire. The party's campaign does not highlight Gaza, focusing instead on education and social issues.

During Livni's Hebrew University speech, several dozen backers of one group that did oppose the war -- the small leftist party Hadash -- rallied outside, though their voices could not be heard in the auditorium.

Members said later that they see no significant differences among the major candidates for leadership in Israel.

"They're two faces of the same coin," said Hanaa Mahamid, 24, a student and an Arab citizen of Israel. "All of them are war criminals."