Mr Bush went into the 34-nation meeting intent on promoting traditional US doctrines of free trade and liberal market economics, with the goal of a giant free trade area, building on the existing agreements, that would stretch from Alaska to the Southern Ocean.
But not far from the sealed-off, massively protected hotel where the leaders met, some 10,000 demo-nstrators marched through the resort city of Mar del Plata. "Get Out Bush," they chanted, in protest not only at the free trade proposals but at the Iraq war and other US policies
"We don't have any confidence in anything Mr Bush might propose here," said Juan Gonzales, an Argentine trade union leader. Whatever emerged, it "will only prolong hunger, poverty and death in Latin America," he said. Among those at the protest rallies were Hugo Chavez, the radical Venezuelan leader and vitriolic critic of the Bush administration, and the legendary Argentinian footballer Diego Maradona.
The US President and Mr Chavez were due to meet later in the day. "I'll be polite to him," was all Mr Bush would say of the man who in Washington has become a bête noire to match Cuba's Fidel Castro.
But tensions were hardly less evident in Mr Bush's joint appearance with his host Nestor Kirchner, the Argentinian President and leader of the country whose economy collapsed beneath a mountain of deficits and debt after adopting US and IMF-backed free market policies in the 1990s.
The two were supposed to answer questions after their meeting. Instead, they delivered separate statements, each stressing how the discussions had been "candid" - diplo-speak for forthright disagreement.
Mr Kirchner later confirmed that impression: "It wasn't a meeting looking for nice words but to speak the truth. We both did just that."
Later however, Mr Bush did face the White House press corps, interested less in the niceties of hemispheric relations than the future of his fragile presidency. The administration's problems were underscored yesterday by three new polls, each putting his approval ratings below 40 per cent, in one case dropping as low as 35 per cent.
Most damning perhaps was a Washington Post/ABC News survey. Not only was the proportion of Americans disapproving of Mr Bush's performance at an unprecedented 60 per cent. Fully 58 per cent, it found, now doubt Mr Bush's honesty and personal integrity.
By a two to one margin, the poll's respondents gave the administration low marks on ethics. The Bush White House, in short, is now seen as no less sleazy than the Clinton administration before it, whose failings Mr Bush vowed during his 2000 campaign never to repeat.
Under a barrage of questions from the US reporters, the President again refused to go into specifics. "We're going through a very serious investigation," was all he would say about the fate of Karl Rove, still under investigation in the affair over the leaking of CIA agent Valerie Plame's name.
"I'm not going to discuss it until it's completed. My obligation is to set an agenda, deal with the problems we face."
Speculation has been mounting that a White House staff shake-up is in the offing, to signal a new start to a second term that - since the summer - has lurched from disaster to disaster; the response to Hurricane Katrina, the indictment of the top aide Lewis Libby, the morass in Iraq and the embarrassing failure of the Supreme Court nomination of Harriet Miers.
But President Bush would not be drawn. "I understand there's a preoccupation with polls," he admitted - only to change the subject to the safer terrain of the war on terror and his ambitions for free trade and democracy in Latin America and beyond.