As the new ceasefire between Israel and the Palestinians limps through its first perilous hours, the United States is facing the formidable task of ensuring that the calm survives to allow for the creation of a war coalition with Arab and Islamic support.
At the centre of their diplomatic crosshairs now stands the battle-scarred figure of ex-general Ariel Sharon, the Israeli Prime Minister, who had been gaining popularity in Washington until the US atrocities, but who has angered much of the international community in its aftermath.
The Americans will press Mr Sharon to take swift measures in response to the ceasefire announced by Yasser Arafat on Tuesday, so that the Palestinian leader has something to offer his people in the hope of convincing them that the last year of death, violence, worsening poverty and ever-tightening military occupation has achieved results.
The signs last night, though, were that Israel has no intention of moving speedily. Although the violence fell sharply yesterday, a government spokesman, Avi Pazner, said the ceasefire had not taken hold because there had been shooting in Gaza and near Hebron and Ramallah. Israel would continue to insist on 48 hours of total calm before going into formal truce talks, he said.
To win over his people, Mr Arafat must do more than flex the extra diplomatic muscle that he acquired on Tuesday by convening 35 foreign diplomats, and announcing a ceasefire.
True, his dismal position has slightly improved: the ability to destabilise the coalition's Arab-Islamic components by returning to violence has given Mr Arafat some needed new political leverage, and he has gained the favour of the US. But none of this matters much on the streets of Gaza or Hebron or Nablus, where Palestinians have been living under an Israeli siege for nearly a year, amid deepening deprivation and a rising death toll, which now comprises more than 600 Arabs, many of them youngsters.
He must persuade them that he has secured far more concrete rewards than this. If not, the truce stands little chance of lasting for long on the ground. Weariness with the intifada has been deepening among Palestinians, but so has militancy.
One well-placed Western source said: "If the Palestinians don't receive anything they are going to go straight back to fighting."
America is expected to press Israel to ease its punitive blockades of the occupied territories and to release tax refunds to the Palestinian Authority, to help to relieve the dire economic conditions. The Palestinians citing the Mitchell recommendations are also certain to demand a full freeze on illegal Jewish settlement building. They will also want international observers to monitor a truce.
The Americans will concentrate their attention on Shimon Peres, Israel's Foreign Minister, whose star has risen steadily in Washington in recent days, just as Mr Sharon's has sunk sent plunging by his military assaults against the Palestinians, and his ill-judged attempt to compare the US tragedy with the Israel-Palestinian conflict.
The pressure is likely to come directly from Mr Bush, rather than the US State Department. "It will have to come from the White House," said one diplomatic source. "They are the only people who have any influence on Sharon."
Even the relationship between the US and Israel the most enduring of geopolitical love affairs has been affected by the American catastrophe.
Israel, by far the largest beneficiary of American foreign funds, has always enjoyed huge support from Washington, not least because of the votes and wealth of the Jewish lobby in the US. While George Bush was considered less pro-Israeli than his predecessor, he had been showing increasing impatience and contempt for Mr Arafat. The Palestinian leader was a regular visitor to the Clinton White House; he has yet to visit the Bushes. By contrast, Mr Sharon once shunned by US officials as an inflexible hardliner, whose career was forever blemished by the Sabra and Chatila massacres slid quickly into Washington's favour once he was elected Prime Minister.
Now, at least for a while, the cards have been shuffled. The overpowering mood of patriot-ism in the United States, unleashed by the fireballs that devoured the World Trade Centre, and the nation's unanimous demands for revenge, have overwhelmed the voice of the pro-Israel lobby.
Mr Sharon's own conduct has contributed to this. Just when America, reeling in pain amid its worst crisis since the Kennedy assassination, wanted him to cool the Middle East conflict to allow coalition building to get under way he postponed truce talks, and began to talk of Yasser Arafat as "our bin Laden".
Washington's instructions to Israel now will be to stay on the sidelines while the coalition coalesces, and to remain apart from whatever military strike they launch.
Both Mr Sharon and Mr Arafat will be under intense international pressure to move swiftly into talks. Israel's foot-dragging will only deepen the international anger over its recent conduct.
The Palestinian militant opposition groups notably Hamas and Islamic Jihad have said that they will not be bound by the truce, although there have also been no suicide bombings since the US attacks.
Both sides know that the fundamental problems that detonated the Palestinian intifada loom as large now as they did one year ago.
No one disputes that the truce that flickered into life yesterday could be snuffed out instantly by one suicide bomb, or one tank shell.Reuse content