George W. Bush made his greatest Middle East mistake before becoming president. Had he embraced rather than disowned Bill Clinton's desperate efforts to secure an agreement, Israeli and Palestinian leaders might have gone the extra mile to accommodate the new administration. The tragedy of the second intifada might have been averted. The seizure of Gaza by Hamas might never have occurred.

Now the US quest for peace has been placed in the hands of diplomats George Mitchell and Christopher Hill, both veterans of the Clinton period. If they dismiss the work of Bush as he did theirs, the result will probably be failure. Significant steps to move toward a settlement could languish and opportunities to achieve a breakthrough could be ignored.

If Mr. Mitchell and Mr. Ross can learn from Bush's mistake and embrace the positive aspects that came from his administration, they could save themselves many redundant steps on the road to peace. If full-dress negotiations do produce accord, the key would then be "shelving" agreement until the Palestinian Authority (PA) reestablishes sufficient control to implement it.

Bush did pave the way for his successors on some fronts. He declared Yasser Arafat "tainted by terror," opening the way for the more moderate Mahmoud Abbas (known as Abu Mazen) to play the lead negotiating role.

Bush was also the first president to publicly endorse a sovereign Palestinian state. He organized the so-called Quartet, consisting of the US, the UN, the EU, and Russia, to backstop the peace process. And he developed a three-stage practical series of steps toward peace, the "road map," beginning with antiterrorism measures and political reform by the PA and a freeze on new settlements by the Israelis. There has been some progress by both sides; much more needs to be done.

Bush also declined to support a "right of return" to Israel for most of the original Palestinian refugees or the complete withdrawal of Israel to its 1967 borders. These will be painful but essential concessions for the Palestinian side.

Exploratory talks between President Abbas and Israeli Prime Minister Ariel Sharon began but made little progress. Convinced that his counterpart lacked political gravitas, Mr. Sharon embarked upon a policy of unilateralism, withdrawing from Gaza and a handful of symbolic West Bank settlements.

Abbas and his ruling Fatah colleagues soon suffered a series of blows at the hands of Hamas, internationally branded as a terrorist organization and committed to the destruction of Israel. Hamas upset Fatah in local elections and then in legislative contests on the West Bank and Gaza. A Saudi-brokered power-sharing accord between the two factions broke apart when Hamas violently took control of the territory.

In a candid review of its failures, the Fatah-dominated PA concluded that the governing authority had operated with no plan for meeting the Islamist challenge. Instead of a laboratory for statehood, the West Bank and Gaza were treated like occupied territories. More than 10 Fatah militias came and went without apparent doctrine or objective.

Despite these serious setbacks, the Bush administration kept the process alive, brokering talks between Abbas and Sharon's successor, Ehud Olmert. In the fall of 2007, Secretary of State Condoleezza Rice invited a group of interested nations to Annapolis, Md. The event was rich in symbolism, confirming what the Saudis, Egyptians, and Jordanians had for months been telling visitors: that Iran worried them far more than Israel, and they were thus prepared to play a constructive role in seeking an end to the Israeli-Palestinian dispute.

Israel's new prime minister, Benjamin Netanyahu, is, like Sharon, a tough guy of the center-right but one publicly committed to a two-state solution. Encouraging reports from the West Bank describe improved commercial dealings between Israelis and Palestinians and credit the PA with taking meaningful strides toward a modern administration, including well-trained security forces.

No one suggests that an accord could be negotiated, ratified, and implemented with Hamas holding Gaza. But after a decent interval, more formal talks might begin with Mitchell and Hill playing activist roles. The starting point might be where the Clinton White House or, perhaps the Taba talks adjourned eight years ago. Most important, if the negotiators do achieve success, it would be wise to keep the deal on the shelf rather than seeking to implement it prematurely. Fatah could then campaign for public support as the only party capable of delivering on the dream of Palestinian statehood.

The downside is, of course, that critics of one compromise or another, or of the entire package, may have months to build opposition to ratification. If the accord is fair, though, the yearning for peace on both sides may well prevail and the pressure on Hamas, not only within the Palestinian community but from such neighboring powers as Jordan and Egypt, could prove decisive.