The Mideast peace summit (search) could yield a series of goodwill gestures and first steps toward calming the violence that erupted 32 months ago, ended peace negotiations and killed more than 3,000 Israelis and Palestinians.
Israel is supposed to agree in principle to a Palestinian state (search) -- a significant concession from Prime Minister Ariel Sharon (search), a hawkish ex-general who has fought the Palestinians all his life.
But the sides differ sharply on how to interpret the immediate steps required by the U.S.-backed "road map" for peace -- and are miles apart on the terms of a final settlement that is to be reached, in its last phase, by 2005.
The disagreements cover issues great and small: Israel wants explicit Palestinian acceptance of its right to be a "Jewish state" -- which would implicitly mean the Palestinians giving up the "right of return" for refugees. The Palestinians are for the moment refusing.
The Palestinians want Israel to dismantle all of the roughly 100 settlement outposts established since March 2001 -- as required by the road map; Israel says it will dismantle only some of them.
The United States, positioned to be the chief arbiter in implementing the road map, has mostly avoided taking sides. Ultimately, much will depend on how sustained and powerful its involvement will be.
But the entire enterprise could be swiftly brought down if Palestinian terror attacks against Israel resume.
The road map, presented to the sides in April, is to be formally launched at Wednesday's meeting in Aqaba, Jordan, where King Abdullah is hosting President Bush, Palestinian Prime Minister Mahmoud Abbas and Sharon.
Here's a look at what is expected at the summit, and what the players hope to gain from a renewed Mideast peace process.
The summit seeks to launch a renewed peace process with Israeli and Palestinian declarations in which each recognizes the other's right to exist and underscores its commitment to peace.
There is also hope for agreement on how to carry out some of the sides' commitments under Phase I of the road map. The ones being focused on are ending attacks against Israelis by Palestinian militias and dismantling the West Bank settlement outposts Israelis have established in recent years.
The United States is expected to lead a sustained monitoring process and press for the further steps required by the road map, which include a complete Israeli freeze on construction in Jewish settlements and a gradual pullout from Palestinian autonomous areas that were occupied in the recent conflict.
THE UNITED STATES:
Bush is determined to implement the vision he outlined a year ago for two states living in peace side-by-side, one Jewish and the other Palestinian. Even before that, though, he accepted the view pressed by Sharon that attacks on Israel must subside and Palestinian security improved before a peace plan could be implemented.
Bush's direct involvement with two summit meetings was prompted partly by victory in Iraq and pressure from Arab and European governments that the administration take a more direct role in pushing Israel to withdraw from Palestinian population centers.
Bush has a lot to gain: diplomatic success would strengthen his standing with Arab countries. Many of them have argued terrorism is partly rooted in Israel's "occupation." Bush does not have to agree with that. But if he gets Israel to give up anything -- outposts, for instance -- it will be a significant signal.
Abbas appears interested in ending the violence -- which has left the Palestinian Authority in ruins -- in exchange for the promise of statehood.
That will require a Herculean persuasion effort -- and perhaps a difficult fight -- with Hamas, Islamic Jihad, the Al Aqsa Brigades that grew out of Abbas' own Fatah movement and a host of smaller groups. He could also face opposition from Yasser Arafat, who still wields considerable influence.
In return Abbas wants a clear Israeli commitment to the road map -- including an end to military operations and to all settlement activity and a pullout from the autonomous Palestinian zones Israel seized during the conflict.
The next phase of the road map could include establishing a Palestinian state on provisional borders still to be determined.
Final borders would come in future peace talks where the Palestinians will apparently raise the same demands that weren't met in the previous talks: all of the West Bank and Gaza, a capital in east Jerusalem, the dismantling of all Jewish settlements and a recognition of Palestinian refugees' "right of return" to Israel.
For most Israelis, the goal is simply an end to the violence that has made nowhere safe in their country. Opinion polls show that for a credible guarantee of peace, a majority would give the Palestinians most, if not all, of what they seek.
Sharon's government, however, hails from the Israeli right, which has traditionally sought to hold on to as much as possible of the West Bank and Gaza.
Sharon's main goal appears to be for Abbas to fully carry out his side of the road map, especially the "dismantlement of terrorist capabilities and infrastructure" -- the very thing Israel's far more powerful military has been trying to do for 32 months.
In return, Sharon appears willing to carry out at least some of his road map obligations, including dismantling some settlement outposts, withdrawing troops from some areas, and at least temporarily cooling military activity.
If this brings an end to terror, Sharon appears willing to agree to a provisional Palestinian state. But few in Israel believe the lifelong hawk and architect of settlement-building can meet the Palestinians' terms for a final peace settlement.
THE ARAB WORLD:
Leaders of Arab countries surrounding Israel are hoping now for a lessening of the tension that has gripped the region since Israeli-Palestinian violence broke out. Fewer TV and newspaper pictures of the violence would calm their publics and reduce the militancy that leads to terrorism -- a major concern in the wake of the U.S.-led war on terror.
It also might ease some of the criticism Western-leaning Arab leaders have faced from their citizens for maintaining close ties to the United States, seen as Israel's main ally.
The U.S.-led war on Iraq has Arabs thinking about how to shore up their relationship with the United States -- not end it as some of their citizens have demanded. That purpose would be served by broader peace with Israel -- which most of the Arab world appears willing to accept as long as the Palestinian issue is settled and Israel returns the Golan Heights to Syria.