...Although Bush endorsed a two-state solution, he did little to promote it, letting the peace process languish until the end of his second term. Bush categorically backed Israeli Prime Minister Ariel Sharon, whose unilateral withdrawal from Gaza strengthened Hamas and undercut those who wanted peace talks.

The administration was solely focused on Iraq, even as Gaza became a virtual prison camp with all borders controlled by Israel. Nor did the administration press Israel to cease expanding settlements on the West Bank.

Under such conditions, Palestinians turned toward Hamas - which at least provided social services. Young Palestinians and intellectuals now talk increasingly about the "one-state solution." Meantime, Hamas' rocketing of Israeli towns has further soured Israelis on the idea of two states.

So Obama will take office as the very idea of two states is dying.

The Gaza war has badly undermined those moderate Arabs who still support the concept, such as Palestinian Authority leader Mahmoud Abbas, and the rulers in Jordan and Egypt.

It's nonsense to believe that Israel can forcibly install Abbas back in charge of Gaza; Abbas would be denounced as a puppet. The Gaza war will also make it harder to revive the 2002 Arab peace plan, which calls for all Arab states to recognize Israel in return for a two-state formula.

And the fighting also has threatened promising mediation by Turkey that had brought Israel and Syria together in renewed peace talks. Embarrassed by the Gaza war, Turkey has suspended the talks.

Yet the arrival of Obama provides a brief window in which a serious peace process might get restarted. He will have to use all his smarts and charisma to restore hope for change in the region and dispel suspicions he's biased.

He must convince skeptical Palestinians and Israelis that Mideast peace isn't a mirage, so they'll vote for peacemakers in upcoming elections. He must also persuade members of Congress not to interfere.

Some of the best advice on how to proceed is offered in a small book called Negotiating Arab-Israeli Peace: American Leadership in the Middle East by Daniel Kurtzer and Scott B. Lasensky (read excerpts at www.usip.org). Kurtzer, a former peace negotiator and U.S. ambassador to Egypt and Israel, is on Obama's short list to become a top Middle East adviser, and I hope he gets the job.

The pair stress that the president must make clear to Americans why Arab-Israeli peacemaking is a priority in a post-9/11 world. Rather than the passivity of the last eight years, the U.S. role should be proactive. It should aim for a final settlement and not get caught up in incremental steps.

The United States should involve other regional and international players in the process, backing Israel-Syria talks, for example, which were long opposed by the Bush team. And U.S. officials must press Israel to meet its commitments, like freezing settlement-building, even as they press Palestinians to cease violence.

Most crucial, the president must be fully behind any policies pursued by his secretary of state or special Mideast emissaries. Despite his full plate, this process won't move without him.

There's still a chance to rescue Mideast policy from eight years of fumbles, and Obama can't afford to miss that chance.