Obama UN Speech: President Obama delivered a stern speech to the leaders of the world’s nations Wednesday morning, challenging them to live up to their responsibilities even as he acknowledged that the United States also has fallen short on many fronts.

Obama defended the actions of his young administration as initial steps toward progress on intractable world problems. And he urged his counterparts to do likewise, calling for “a new era of engagement based on mutual interest and mutual respect.”

“Make no mistake: this cannot solely be America’s endeavor,” Obama said. “Those who used to chastise America for acting alone in the world cannot now stand by and wait for America to solve the world’s problems alone.”

Obama discussed issues of nuclear proliferation, peace and security, climate change and global growth and development. He drew applause when he talked about how his administration had banned torture of terror suspects, and was engaging with the United Nations in a more complete way than the U.S. did during the Bush administration.

But the new U.S. president also acknowledged that the United States and its world partners over time have failed to confront some of the world’s problems seriously.

“If we are honest with ourselves, we need to admit that we are not living up to that responsibility,” Obama said.

” . . . We can be remembered as a generation that chose to drag the arguments of the 20th century into the 21st; that put off hard choices, refused to look ahead, and failed to keep pace because we defined ourselves by what we were against instead of what we were for. Or, we can be a generation that chooses to see the shoreline beyond the rough waters ahead; that comes together to serve the common interests of human beings, and finally gives meaning to the promise embedded in the name given to this institution: the United Nations.”

The speech was Obama’s first address to the General Assembly. His audience included several foreign leaders his administration is seeking to face down on the diplomatic front. Among them was Iran’s president, Mahmoud Ahmadinejad, who has rebuffed the world’s calls to stop enriching uranium and has thumbed his nose at U.S. criticism of his country’s human rights record, his hostility toward Israel and his support for terrorism.

Also present was Libyan leader Moammar Gaddafi, whose hero’s welcome for the recently-released Lockerbie bomber has renewed American anger toward his leadership. And Hugo Ch?vez of Venezuela, whose friendly greeting and handshake with Obama at a summit in Trinidad was a public relations gaffe for the president.

Obama singled out Iran and North Korea in his remarks about the need to halt the spread of nuclear weapons, saying that both nations must be “held accountable” if they refuse to abide by international arms treaties.

He cited his own status as the first black U.S. president in issuing a call to respect human rights and democratic government around the globe — an apparent reference to Ahmadinejad’s violent clampdown on public demonstrations after elections this summer.

“True leadership will not be measured by the ability to muzzle dissent, or to intimidate and harass political opponents at home,” Obama said. “The people of the world want change. They will not long tolerate those who are on the wrong side of history.”

” . . . As an African-American, I will never forget that I would not be here today without the steady pursuit of a more perfect union in my country,” Obama continued. “That guides my belief that no matter how dark the day may seem, transformative change can be forged by those who choose the side of justice.”

U.N. Secretary General Ban Ki Moon opened Wednesday’s session by reciting a grim litany of crises the world has confronted in the past year — food and energy shortages, global recession, global warming and pandemic flu — to highlight the need for a “spirit of renewed multilateralism.”

“Now is our time,” he said.

Ban urged the world leaders to secure a pact on climate change, approve a ban on nuclear testing and reverse the slide into grinding poverty of workers who are already teetering on the edge of economic instability.

“Markets may be bouncing back, but incomes and jobs are not,” Ban said. “an estimated 100 million people could fall below the poverty line this year.”

Ban chided Burma for failing to release detained Burmese opposition leader, Aung San Suu Kyi, saying the military junta’s recent decision to release of dozens of political prisoners did not go far enough. And he said that issues of “justice and accountability” during Israel’s invasion of Gaza last winter need to be addressed.

The United States recently opposed a proposal by a U.N. rights investigator, South African justice Richard Goldstone, to open a war crimes investigations against Israel and Hamas. The United States and Israel both said Goldstone’s mandate was biased.

Ali Treki, a senior Libyan official who is serving as president of this year’s 192-member General Assembly, delivered a measured opening statement — notable because it did not single out the United States or Israel for criticism.

“We are determined to work together for effective and strengthened organization that is responsive to the daunting challenges facing the world today,” he said.