As two senior US officials tour the Middle East, the BBC's Roger Hardy finds experts are downbeat about the prospects for reviving the Israeli-Palestinian peace process.
The US is seeking to bolster the Fatah leadership
In a speech in mid-July, President George Bush reaffirmed his commitment to a two-state solution, with a Palestinian state living side by side with Israel.
Now, Secretary of State Condoleezza Rice and Defence Secretary Robert Gates are trying to give some substance to this pledge.
The aim of their visit to the region is, first, to create an alliance of "moderates" to counter the influence of Iran and Syria and the militant groups Hamas and Hezbollah.
And, second, they are trying to breathe life into the peace process.
They want to persuade the Arab states to attend a proposed regional meeting - the White House is avoiding the word "conference" - which Ms Rice will host in the autumn.
This will bring together Israel, the Palestinians and some of the Arab states.
Egypt and Jordan already have diplomatic relations with Israel. The hope is to draw in the Saudis, who do not.
But visit the foreign-policy think-tanks in Washington and you will not find many optimists.
Ellen Laipson, a former senior official in the National Security Council who now runs the Henry Stimson Center, reflects the general scepticism.
"I think the Bush administration has created a myth about itself," she says, "that it believes more deeply in a Palestinian state than previous presidents."
"Yet there is no sign they are really going to make the deep investment in peace-making that it would require."
Moderates and radicals
It appears the Bush initiative is still a work in progress.
It is not wise... to build up Hamas by making their opponents the favourite sons, if I can put it this way, of the West
Ambassador Thomas Pickering
It is not clear where or when the proposed regional "meeting" will take place - or, crucially, who will attend.
What inducements might persuade the Saudis to turn up?
Will Syria even be invited, given the current frostiness between Washington and Damascus?
No less fundamental, who can speak for the Palestinians at a time when they are governed by two rival administrations?
The Americans and the Israelis want to strengthen what they regard as the moderate government appointed by President Mahmoud Abbas in the West Bank - and isolate and weaken the Hamas administration in Gaza.
David Makovsky, of the pro-Israeli Washington Institute for Near East Policy, thinks it is vital to support President Abbas and his prime minister, Salam Fayyad.
"Hey, we got a moderate on the Palestinian side, we got a moderate on the Israeli side - and we still do nothing?"
That would simply guarantee, he says, that the radicals would prevail.
Will and staying power
But one of Washington's foreign-policy veterans, Thomas Pickering, is not convinced this approach will work.
"It is not wise for us, in a back-handed way, to build up Hamas by making their opponents the favourite sons, if I can put it this way, of the West."
Ambassador Pickering was under-secretary of state in the Clinton administration.
He thinks the two key figures - President Abbas and Israeli Prime Minister Ehud Olmert - may be politically too weak to carry the burden of peace-making.
The Bush administration is having its work cut out convincing the doubters that - with less than 18 months left to run - it really does have the will and the staying power to revive hopes for peace.