The hastily convened conference opening Tuesday in the Hague, Netherlands brings together all the countries bordering Afghanistan, including Iran, and all nations contributing troops to the NATO-led international force fighting Taliban insurgents.
It will be opened by U.N. Secretary-General Ban Ki-moon and Afghan President Hamid Karzai.
"We have great expectations," Karzai said after arriving Monday night. "I'm sure there will be support for Afghanistan ... and that together, Afghanistan and the international community will strive and succeed towards the completion of this journey together."
With the meeting scheduled to last just seven hours including lunch, few countries will be able to give a nuanced analysis on the conference's stated theme: a comprehensive review of Afghan strategy in a regional context. Most will not have a chance to speak at all.
U.S. Secretary of State Hillary Clinton was expected to outline the policy review unveiled last week by President Barack Obama. The president said he will send an extra 17,000 soldiers and 4,000 advisers to train Afghan military forces, plus hundreds more civilians to work on development issues. More than half of the 70,000 troops now in Afghanistan are Americans.
Despite its brevity, Holbrooke said the "big tent meeting" in The Hague is "tremendously important," and its success already was guaranteed by the lengthy list of attendees.
"The very fact that they are here signals that the world has not forgotten Afghanistan, and that now we know that Pakistan is part of the issue," he said.
Of the 73 nations invited, only Uzbekistan has declined to come, organizers said Monday.
Holbrooke called the conference "the launch point for the international recommitment to the effort in Afghanistan and western Pakistan."
Unlike previous international conferences, the Hague meeting was not intended to raise money or troops — issues that may be raised at subsequent meetings including a NATO summit next weekend.
But Holbrooke said the U.S. administration is devoting much thought to financing the Afghan operation.
"The current costs of the Afghan security forces vastly exceed the capacity of the governments that support them," he said.
Holbrooke declined to be drawn on the potential implications of the meeting for U.S.-Iranian relations, which he called "a work in progress." But he said Iran was a crucial player that had to be included.
"How can you talk about Afghanistan and exclude one of the countries that is a ... neighboring state," he said after meeting the conference host, Dutch Foreign Minister Maxime Verhagen.
Last week, the U.S. State Department ruled out any "substantive meeting" between U.S. and Iranian officials.
On Monday, Clinton declined to rule out any meeting with Iranians during the conference. "I have no plans" to seek out Iranian diplomats. "I can't forecast tomorrow," she said.
Obama recently sent a message to Iran expressing the desire for better relations and American officials are closely watching Tehran's reaction.
"The fact that they accepted the invitation to come suggests that they believe there is a role for them to play, and we're looking forward to hearing more about that," Clinton said.
Deputy Foreign Minister Medhi Akhundzadeh, who leads the Iranian delegation, said Afghans held the key to the future of their nation, not the international military force fighting the Taliban.
"The presence of foreign troops can't bring the peace, security and stability to the country," Akhundzadeh said, in comments translated from Farsi.
Iran has an interest in stemming the flow of refugees and drugs across its 580-mile (930-kilometer) border with Afghanistan, said Willem Post, senior analyst at the Clingendael Institute think tank in The Hague.
At the same time, Obama has an interest in sharing the burden, and Europe should accept the chance to deepen its engagement with the Obama administration, he said.
"There is a real risk that otherwise the military surge and civilian surge will become Americanized," Post said. "We are all in this together."
Holbrooke and Verhagen made it clear U.S. involvement was not a one-way street, and that Afghanistan had a contribution to make: cracking down on corruption and cleaning up its political system to ensure a free and fair presidential election later this year.
"Afghanistan can and must do better," said Verhagen, whose country has contributed 1,600 soldiers to the NATO-led international force.
Clinton said that although Tuesday's meeting was not designed as a fundraiser, she planned to formally pledge $40 million from the U.S. government to help fund the election.