President Biden Urges Unity in Confronting Global ChallengesBiden, taking his place for the first time as head of state before the U.N.’s distinctive green marble rostrom, also used his half-hour speech to push for aggressive actions against COVID-19 and climate change. “This is a clear and urgent choice that we face here at the dawning of what must be a decisive decade for our world, a decade that will quite literally determine our futures,” he said. “As a global community, we're challenged by urgent and looming crises wherein lie enormous opportunities if -- if -- we can summon the will and resolve to seize these opportunities.” Without mentioning his nation’s greatest adversary -- China -- by name, Biden also vowed that he would not seek to escalate conflict. In an earlier speech before the General Assembly, U.N. Secretary General Antonio Guterres said it would be “impossible to address dramatic economic and development challenges while the world’s two largest economies are at odds with each other” “We're not seeking -- I’ll say it again -- we are not seeking a new Cold War or a world divided into rigid blocs,” President Biden said. “The United States is ready to work with any nation that steps up to pursue a peaceful resolution to shared challenges, even if we have intense disagreements in other areas, because we'll all suffer the consequences of our failure if we do not come together to address the urgent threats like COVID-19, climate change or enduring threats like nuclear proliferation.” ‘We’ve turned the page’ Biden also defended his controversial decision to withdraw forces from Afghanistan after 20 years of American involvement there. Those comments were noted by Afghanistan’s ambassador to the U.N., Ghulam Isaczai, who was appointed by the previous government, before the Taliban seized power last month. The White House has said that they are in “no rush” to recognize the Taliban as the official government. “I stand here today, for the first time in 20 years, with the United States not at war,” Biden said. “We've turned the page.” Biden’s appearance on Tuesday was a direct rebuke to the aggressive “America first” doctrine of his predecessor, Donald Trump. “As we look ahead, we will lead,” he said. “We will lead on all the greatest challenges of our time from COVID to climate, peace and security, human dignity and human rights. But we will not go it alone. We will lead together with our allies and partners in cooperation with all those who believe as we do, that this is within our power to meet these challenges, to build a future, to miss all of our people and preserve this planet.” The annual assembly at U.N. headquarters in New York is arguably the biggest global stage for world leaders, with leaders using their time to expound on topics of global and regional interest before the 193-member assembly. This year, only about 100 heads of state announced they would attend in person: the leaders of China, Iran, Egypt and Somalia are among a handful of those delivering pre-recorded comments. Ideals vs reality But Biden’s globalist, cooperative, optimistic vision clashes with awkward reality. On Friday, America’s oldest ally, France, recalled its ambassadors to the U.S. and Australia, expressing anger over the “stab in the back” delivered by those two nations when their nuclear submarine deal nullified a nearly $70 billion French-Australian deal for conventional submarines. White House Press Secretary Jen Psaki said Biden will soon hold a phone call with his French counterpart, President Emmanuel Macron, who is not planning to travel to New York. She declined to say whether the Biden administration would be making a compensatory gesture to France. Biden will also meet Tuesday on the sidelines of the U.N. event with Australian Prime Minister Scott Morrison. Later Tuesday, he will meet in Washington with British Prime Minister Boris Johnson. Later in the week, separate from the UN meeting, Biden will host a summit on COVID-19, and will also meet with both Indian Prime Minister Narendra Modi and Japanese Prime Minister Yoshihide Suga. Those two are members of the so-called “Quad,” a strategic dialogue that also includes Australia, and is seen as a bulwark against growing Chinese influence. U.N. correspondent Margaret Besheer contributed from New York.