“I would be surprised if he were more rather than less forthcoming in dealing with Israel,” Bob Zelnick, a former Middle East correspondent for ABC News who now teaches at Boston University, said of Mr. Obama. “My sense is that he both dislikes and distrusts Israeli Prime Minister Netanyahu, and that he is more likely to use his new momentum to settling scores than to settling issues.”

On Iran, the immediate concern here is that a White House pursuit of bilateral talks would stretch out the timetable for diplomacy even as Mr. Netanyahu’s famous “red line” for halting Iran’s capability to develop a nuclear weapon closes in. On Wednesday, one member of the inner circle of Iran’s ruling system said such talks — the subject of an October article in The New York Times — are “not a taboo,” though another said it was a “big mistake” for Washington to think it could “blackmail” Iran into relations.

Several analysts said Mr. Obama was loath to take on a new Middle East military operation; indeed, one of the biggest applause lines in his victory speech was his declaration that “a decade of war is ending.”

Regarding the Palestinians, Israeli officials had been counting on the Obama administration to forcefully oppose the United Nations bid — as it did last year — and to chastise those countries that support it. But Palestinian leaders seemed unworried on Wednesday, making the bid for nonmember state status in the General Assembly a central focus of their congratulations.

“We will not retract,” said Saeb Erekat, the chief Palestinian negotiator. “We hope President Obama will even support this move.”

Regardless of how he handles the United Nations effort, Mr. Obama is unlikely to pursue the peace process more broadly in the early part of his second term, given the turmoil across the Middle East and internal divisions among the Palestinians.