Families of soldiers and civilians killed in last year's war in Lebanon held a memorial ceremony at Israel's national military cemetery.
The war cost Olmert most of his popular support and could yet cost him his job. Two other wartime leaders who have already been forced out of office ex-Defense Minister Amir Peretz and ousted army chief of staff Dan Halutz joined the gathering at Jerusalem's Mount Herzl cemetery.
Peretz's replacement as defense minister, Ehud Barak, gave his first major address since taking office June 19. He implied criticism of the war, noting that families of fallen soldiers always ask questions after a conflict: "Was it necessary? Was there any other way? Did politicians do everything, everything, to prevent the casualties? Was the army ready?"
He said the "inquisitive" Israeli society "demands answers to these questions."
Barak appeared to be referring to the upcoming report of a government commission of inquiry. In its initial findings, the commission was highly critical of Olmert. The final report is due next month, and Barak has said he will pull his Labor Party out of Olmert's government, probably forcing elections, unless Olmert resigns by then.
Barak paid tribute to the 160 Israelis killed in the fighting. Between 1,035 and 1,191 civilians and combatants were killed in Lebanon during the war.
Dalia Itzik, speaker of the Israeli parliament and acting president, acknowledged that "mistakes and failures" plagued the war. She also appealed to the leaders of Hezbollah to give a first sign of life from two soldiers it captured at the outset of the war.
Families sat quietly on folding chairs, marking the anniversary of the start of the war according to the Hebrew calendar. The main gathering was preceded by smaller ones at sites where Israelis were killed during the war a village near the border and the Haifa train station.
Halutz stepped down after an internal army inquiry was completed. Peretz, who like Olmert lost most of his backing because of the unpopular war, was deposed by Labor, which chose Barak, an ex-army chief and premier, to replace him as defense minister.
Both deposed leaders attended the Jerusalem ceremony, making Olmert all the more conspicuous by his absence.
Aides said that if Olmert had taken part, security precautions at the site would have been prohibitive. Many relatives of the fallen soldiers rejected that explanation.
"I didn't expect the prime minister to show up," said Eliphaz Byeloa, whose son Nadav was killed in a battle in south Lebanon. "I didn't expect him to accept our invitation and request, because I think ... he's a coward. He does not have the courage to look the bereaved families in the eye."
In addition to security concerns, Olmert social affairs adviser Vered Swed explained the premier's absence by citing a policy that the prime minister attends only the ceremony for fallen soldiers of all wars on Israel's annual Memorial Day.
"He can't go to a ceremony for one war and not another, insulting the other families. That's why a unified ceremony was set for that day," she told Army Radio.
The 34-day war began July 12, 2006 with a cross-border raid by Hezbollah guerrillas from Lebanon, attacking an Israeli army patrol, killing three soldiers and capturing two others.
Olmert quickly ordered a full-scale assault on Hezbollah, with the Israeli air force bombing Lebanese infrastructure and a Hezbollah neighborhood in Beirut as well as targets nearer the border.
Hezbollah hit back with nearly 4,000 rockets at northern Israel.
Olmert pledged to win return of the soldiers and crush Hezbollah, but neither goal was achieved.
The government commission faulted Olmert for "hasty" decisions and lack of consultations.
It also blamed Halutz, a former air force chief, for relying too heavily on air power and giving overly rosy predictions to the Cabinet, and Peretz for failing to challenge the military or take a more aggressive part in the decision-making process.