Instead, the administration relied on Egypt's untested Islamist President Mohammed Morsi who—like the Gaza Strip's rulers, Hamas—is a member of the Muslim Brotherhood.
The challenge illustrates America's weakened influence since last year's Arab Spring as popular Islamist political movements have replaced pro-U.S., secular strongmen throughout the region over the last two years. The shift has shaken the foundations of American security strategy in the Middle East and is having its greatest effect in Egypt, the Arab world's most populous and influential country. There, the United States long partnered with Mubarak and his circle of top generals in mediation efforts between Israel and the Palestinians but now faces far trickier diplomacy with Morsi.
President Barack Obama spoke with Morsi Wednesday, but they came out of the discussion with diverging messages. A White House statement credited Egypt's "central role in preserving regional security" while stressing that Obama condemned Hamas' rocket fire from Gaza into Israel and backed the Jewish state's right to self-defense.
But Morsi, speaking Thursday in Cairo, provided a far different account of his conversation with Obama. He said he told Obama that Israel's offensive must stop and should not be repeated and that the leaders "agreed that Egypt and the United States will work together to prevent any escalation or the continuation of the aggression," according to a presidential statement. By "aggression," Morsi meant Israel's military action. Later he even more explicitly denounced Israel's "unacceptable aggression" and sent his prime minister to Gaza in a show of support for Hamas' rulers.
Morsi, who entered office in June, belongs to the Muslim Brotherhood party. Hamas is the Brotherhood's Palestinian chapter and has long been branded a terrorist organization by the United States, meaning American officials have no contacts with the group's members and must work through intermediaries like Egypt, Turkey and European countries to send it messages.
"There is a very clear path here to ending the violence and that's for the rocket attacks to stop, so we would hope that that's a message that would be delivered," State Department spokesman Mark Toner said, referring to the planned visit to Gaza on Friday by Egyptian Prime Minister Hesham Kandil.
Responding to a barrage of missiles from the Gaza Strip, Israel's offensive began Wednesday with sorties that killed Hamas' military commander and destroyed dozens of rocket launchers. But Palestinian militants launched nearly 150 more rockets at Israel on Thursday, killing three people and firing into the Tel Aviv area for the first time since Saddam Hussein's Scud missiles struck Israel's largest city in the 1991 Gulf War.
Late in the day, Israel signaled a ground operation may be imminent as forces moved toward the border area with Gaza, raising the likelihood of a wider conflict following two days in which 15 Palestinians were killed.
Obama was to speak with both Morsi and Netanyahu again Thursday, a U.S. official said, speaking on condition of anonymity because he wasn't authorized to speak publicly on the matter. The president was likely to stress similar points, with White House press secretary Jay Carney repeating the administration's assertion Thursday that there is no justification for missile strikes against Israel.
"The onus here is clearly on Hamas," Toner said. "This is a situation that they've created by firing rockets at innocent Israeli civilians."
The violence in Gaza and Israel adds to the instability plaguing the Middle East and North Africa. Syria is stuck in a civil war that has killed more than 36,000 people since March 2011, according to activists. Libya is awash with militants a year after Moammar Gadhafi's demise, a danger illustrated by the Sept. 11 terrorist attack in Benghazi that killed a U.S. ambassador and three other Americans. Northern Mali has been seized by al-Qaida-linked rebels. Lebanese politics are in disarray. Popular discontent persists in places from Jordan to Bahrain. And Iran's continued international meddling and nuclear program has the U.S., Israel and Arab countries alike on alert.
In previous times of upheaval, Washington could count on a strong ally in Cairo. Despite his abysmal democracy and human rights record, Mubarak played a key role over his three-decade autocracy in promoting Arab-Israeli peace and helping the U.S. fight al-Qaida and contain the influence of Iran. U.S.-Egyptian cooperation has waned on all fronts since Mubarak's February ouster, but Toner said Thursday that Egypt will uphold the 1979 Camp David Accords with the Jewish state.
"We believe the government of Egypt remains committed to its peace treaty with Israel," he said.
Still, Morsi's public comments thus far have inspired little confidence. U.S. officials say they've been confused by Morsi's messaging but remain hopeful that his government will impress upon Gaza's militant leaders the need for a cease-fire. His comments were less inflammatory, however, than the head of the Muslim Brotherhood, Mohammed Badie, who referred to Israel as "the project of the devil" in a speech Thursday in Sudan.
Morsi, Egypt's first freely elected president, is in a tight spot of his own. Opponents at home want him to take a stronger stand against Israel, but many in the establishment fear greater friction with the U.S., which provides Egypt with $1.5 billion in aid each year. That money is dependent on Egypt upholding its peace deal with Israel, one of the Obama administration's key remaining elements of leverage in a changing Middle East.
Associated Press writer Matthew Lee contributed to this report.