Cuba took over leadership of the Nonaligned Movement Friday, but with Fidel Castro too sick to promise an appearance, his younger brother and his good friend Hugo Chavez were left to mete out the anti-American invective. Presiding over the meeting of more than 50 presidents and prime ministers, acting President Raul Castro said the world today is shaped by irrational American desires for world dominance. "When there no longer is a Cold War, the United States spends one billion dollars a year in weapons and soldiers and it squanders a similar amount in commercial publicity," he said. "To think that a social and economic order that has proven unsustainable could be maintained by force is simply an absurd idea." The big question was whether the 80-year-old Castro would be healthy enough to show up for the summit dinner, let alone guide the group during Cuba's three-year chairmanship. The ailing revolutionary leader is under doctors' orders not to preside over the summit, but could still make an appearance, Cuba's foreign minister told the assembly. Raul Castro has settled into his new leadership role, giving several speeches calling for unity against US policies. And Chavez, still campaigning for Venezuela's bid to join the UN Security Council, has repeatedly asserted himself as the natural heir to Castro, who remains a hero to leftists around the world for supporting their struggles. "To be radical is not to be insane, it's to go to our roots. Let's go to our roots, let's be truly radical," Chavez told diplomats and leaders from two-thirds of the world's countries. He concluded by chanting "Patria o Muerte!" - "Fatherland or Death!" - a favored Castro rallying cry. The 118-nation group gave Raul Castro a round of applause, and Malaysian Prime Minister Abdullah Ahmad Badawi expressed satisfaction that the movement "will once again be in Cuba's very capable hands." "Cuba's fight for liberation from imperialism has been a source of inspiration for the world's peoples," Iranian President Mahmoud Ahmadinejad told the assembly. But in the United States, the administration of President George W. Bush tried Friday to hasten the end of the Castro government, proposing that Cubans hold a referendum to decide if they want to be ruled by Raul Castro. The suggestion faced certain rejection by the island's communist leadership, which didn't immediately address it at the summit. Castro temporarily handed power to his 75-year-old brother and a handful of other top officials after emergency intestinal surgery in July. And while Cuban officials praise his recovery and raise expectations of a return to power, Fidel has remained out of sight this week. He's appeared only in photos and video in state media, wearing pajamas while meeting Chavez and UN Secretary-General Kofi Annan. Annan told the group that the world has changed dramatically since Cuba last hosted the movement in Havana 27 years ago, and that developing nations have new responsibilities to promote democracy, protect human rights and develop civil societies. "The collective mission of this movement is more relevant than ever," Annan said. The Nonaligned Movement was formed during the Cold War to establish a neutral third path in a world divided by the United States and the Soviet Union. It now counts 118 members with the addition of Haiti and St. Kitts this week. With next week's UN General Assembly session in New York looming, Chavez and Ahmadinejad called on Nonaligned nations to support Venezuela's security council bid and provide more balance at the UN Both said the veto power of the United States has made the council a toothless promoter of US policy. "The US is turning the security council into a base for imposing its politics," Ahmadinejad complained, according to the official translation of his speech in Farsi. Chavez has been increasingly outspoken at the summit the need to change the membership of the UN Secabout next week's UN General Assembly session in New York, where nations will debate Iran's nuclear ambitions and Venezuela's campaign against Guatemala for a rotating security council seat. Guatemalan Vice President Eduardo Stein told The Associated Press in an interview Friday that his country has secured 90 of 128 necessary votes, and denied that US support for Guatemala's bid has made his country a "puppet" of Washington. Venezuela, however, is confident it will win the seat. Guatemala has stressed its conciliatory foreign policy in the UN campaign, while Chavez has made it clear if chosen for the security council, Venezuela would support Iran in its high-stakes standoff over its uranium enrichment. Venezuela will stand with Iran if the Middle Eastern country is invaded, Chavez said, just as it has pledged to defend Cuba. "Iran is under threat; there are plans to invade Iran. Hopefully it won't happen, but we are with you," Chavez told Iranian President Mahmoud Ahmadinejad. It was not clear what Chavez would do for Iran. He's vowed to cut off Venezuelan oil supplies to the US if it invades Cuba.