WASHINGTON — Two days after John McCain told a leading pro-Israel lobby that he would toughen sanctions against Iran, Barack Obama assured the same group of his commitment to protect Israel against the Iranian threat.
"I will do everything in my power to prevent Iran from obtaining a nuclear weapon," the presumptive Democratic presidential nominee told thousands of members of the American Israel Public Affairs Committee in Washington.
"Let there be no doubt: I will always keep the threat of military action on the table to defend our security and our ally Israel," he said.
Addressing AIPAC -- long considered one of Washington's most influential lobbies -- has become almost a requirement for presidential candidates seeking the Jewish vote. But there was an added imperative for Obama, who has battled accusations that he is overly sympathetic to the Palestinian cause and too willing to negotiate with Iran's controversial president, Mahmoud Ahmadinejad.
McCain, the presumptive GOP nominee, has made the latter charge a centerpiece of his critique of Obama's qualifications to be president.
On Wednesday, Obama gave a full-throated defense of his plan to engage Iran more directly, arguing that the Bush administration's policies have destabilized the Middle East and jeopardized U.S. and Israeli security.
"There are those who would continue and intensify this failed status quo, ignoring eight years of accumulated evidence that our foreign policy is dangerously flawed," Obama said, taking a swipe at his Republican rival.
"I would be willing to lead tough and principled diplomacy with the appropriate Iranian leader at a time and place of my choosing -- if, and only if, it can advance the interests of the United States," he continued. "Only recently have some come to think that diplomacy by definition cannot be tough. They forget the example of Truman and Kennedy and Reagan. These presidents understood that diplomacy backed by real leverage was a fundamental tool of statecraft."
Obama drew frequent and sustained applause for such comments, but it was his repeated proclamations of support for Israel that evoked the biggest ovations. He cited his own youthful search for his roots to explain his admiration for the Jewish state, and he recalled that his great-uncle was among the U.S. soldiers who liberated the Buchenwald concentration camp in Germany in 1945.
Turning to the contemporary impasse in the Middle East, Obama criticized the Bush administration for neglecting the peace process.
"I won't wait until the waning days of my presidency," he said. "I will take an active role and make a personal commitment to do all I can to advance the cause of peace from the start of my administration."
Obama also talked of isolating Hamas, the militant group that controls the Palestinian government, and confronting Syria, which has provided support to Hamas.
And he endorsed an "undivided" Jerusalem as Israel's capital, a position often associated with the right wing of Israeli politics.
"I wonder if he really means it," said Michael Oren, a senior fellow at the Shalem Center, an independent think tank in Jerusalem. "Even Bush doesn't use the U-word. It may come back to haunt Obama if he wins."
Palestinian leaders have long insisted that East Jerusalem, which was captured by Israel in the 1967 Middle East war, be the capital of a future Palestinian state.
Saeb Erekat, a veteran Palestinian negotiator, noted acerbically that even Israeli negotiators have for years discussed various formulas for dividing the city. Obama, he said, was trying to be "more Israeli than the Israelis."
The Illinois senator's speech appeared likely to strengthen his outreach efforts to a crucial group of voters in this country. According to polling conducted by Gallup in April, Obama holds a 61% to 32% edge over McCain among Jewish voters.
But that is still a substantially smaller margin of support than that enjoyed by the 2004 Democratic presidential candidate, Sen. John F. Kerry, who outpolled President Bush 78% to 22% among Jewish voters.
Times staff writers Richard Boudreaux in Jerusalem and Maeve Reston in Baton Rouge, La., contributed to this report.