The United Nations General Assembly this week will draw heads of state, foreign ministers and other leaders from at least 123 countries -- one of the busiest sessions ever, according to UN Secretary General Ban Ki-moon.
Ban cautioned, however, that the "general debate" held Tuesday through Oct. 1 comes at "a time of turmoil and transition."
The 193-nation body, founded to promote and maintain peace after the atrocities of World War II, opens another season with unrest in the Middle East, hot spots in Africa, and economic and political instability worldwide.
A host of thorny new issues are to be discussed -- just days after anti-American protests raged over release of an amateur film disparaging Islam's prophet, Muhammad. One attack in Libya killed U.S. Ambassador Christopher Stevens and three other Americans.
Adding to the global volatility, Syria's civil war has gotten worse, Iran's nuclear ambitions are resurfacing in the face of an increasingly edgy Israel, and the Israeli-Palestinian conflict still boils. "The deteriorating situation in Syria will be foremost in our minds," Ban said.
Last week, the Independent International Commission of Inquiry on Syria told the UN Security Council that the fighting and humanitarian crisis in Syria has intensified since a government crackdown on dissent deteriorated into civil war.
The UN estimates 19,000 people have been killed in the conflict since the Arab Spring protests broke out in March 2011, and Syrian tanks began rolling into population centers in Homs, Aleppo and Hama.
"Gross violations of human rights have grown in number, in pace and in scale," said Paulo Pinheiro, who chairs the UN Commission of Inquiry. "Civilians, many of them children, are bearing the brunt of the spiraling violence."
The inability of the UN to stop the violence being committed in a key member state has become a symbol of the organization's impotence, particularly in the 15-member Security Council, where five countries -- the United States, Great Britain, China, France and Russia -- hold veto power.
President Barack Obama is scheduled to be the second speaker to address the General Assembly on Tuesday, after Brazil, which traditionally opens the discussion.
Israeli Prime Minister Benjamin Netanyahu has asked Obama to state where he would draw a "red line" -- a threshold Iran would have to reach in its uranium enrichment program in order to trigger a decisive U.S. response.
Obama, who UN officials said will depart from his usual practice of meeting with world leaders during bilateral talks and hosting a luncheon, is instead going to deliver his address and then attend the annual meeting of former President Bill Clinton's Global Initiative, which helps address poverty, disease and other concerns.
Obama's short visit was dubbed "drive-by UN diplomacy" by Foreign Policy magazine, referring to the president's lack of availability to many leaders, including Netanyahu and Egypt's newly installed president, Mohammed Morsi.
Stewart M. Patrick, a fellow at the Council on Foreign Relations in Washington, D.C., said Obama is walking a political tightrope in keeping such a sparse UN schedule.
"It would be very difficult for the president to meet with the Egyptian leader without meeting with the Israeli prime minister," Patrick said in an interview published on the think tank's website.
"There's definite antipathy on a personal level, it would appear, between Mr. Obama and Mr. Netanyahu, and certainly, if the president had any desire to meet the Israeli prime minister, he could have already signaled he would do so."