By Jamie Coomarasamy
BBC News, Mar del Plata
Venezuelan President Hugo Chavez is licking his lips in anticipation of what he has predicted will be a "delicious debate".
The summit is a chance for the US to reassert itself
The US government may not see it in quite those terms, but discussions are likely to be lively as leaders from 34 nations meet in Argentina over the next two days.
Much of the debate will centre on how to meet the goal of the fourth Summit of the Americas: "Creating jobs to fight poverty and strengthen democratic governance".
American officials want to steer the discussion away from the Venezuelan leader - National Security Adviser Stephen Hadley said the summit "is not about Chavez" at pre-summit briefings.
But they are aware the US will be pitching its vision of how to alleviate regional poverty, against that of the man who has largely replaced Fidel Castro as Washington's regional bugbear.
In his keynote speech, US President George Bush will argue that the way to guarantee prosperity is by encouraging free trade and a flourishing private sector - and by deepening democracy - although he has acknowledged that efforts to form a Free Trade Area of the Americas have stalled.
Mr Bush will be calling for the other participating countries to demonstrate a commitment to those principles, but he also hopes to demonstrate Washington's commitment to its closest neighbours.
This is the president's first visit to the region since his re-election a year ago.
Following the attacks of 11 September 2001, the perception has grown that - in concentrating so much of its diplomatic energy on the Middle East - the US government has neglected its own backyard.
Whether justified or not, that perception has been to the advantage of Hugo Chavez, who has filled the void with a steady stream of populist, anti-American rhetoric and real offers of economic help to his neighbours, thanks to his country's abundance of oil.
And - with left-leaning governments mushrooming in the region - Mr Bush will be aware that it's becoming an increasingly difficult place to sell the US' vision of how to close the poverty gap.
The Chavez vision is not viewed in exclusively positive terms.
But the Venezuelan leader has tapped into a popular feeling of anger at the "Washington consensus" - the sort of measures which the IMF and other international finance organisations encouraged Latin American countries to adopt.
Those policies are blamed for the economic problems which have resulted in the average GDP in the region being $3,200 - less than a tenth of that of the US.
The Venezuelan leader will be addressing the demonstrators who are expected to converge on the resort of Mar Del Plata on Friday; among them the host country's best-known football star turned talk show presenter, Diego Maradona.
They will be bringing with them a list of grievances against the US, from a belief that globalisation hurts the poorest to anger about the war in Iraq.
And US officials are concerned that the noise they will make will drown out the debate at the summit - however delicious it is.