At President Bush’s first National Security Council meeting in January 2001, he announced that he did not want to be drawn into the shattered Middle East peace process, people at the meeting recalled, because he believed that former President Bill Clinton had pushed so hard for an Israeli-Palestinian accord that he made the situation worse.

Vice President Dick Cheney and Defense Secretary Donald H. Rumsfeld agreed with the president, while Secretary of State Colin L. Powell countered that even if the breakdown in peace talks during Mr. Clinton’s term helped lead to the second Palestinian intifada, or uprising, the United States could not stay aloof.

Condoleezza Rice, the new national security adviser, kept silent, but privately she shared Mr. Bush’s views.

“There was absolutely no prospect of a Middle East peace process that was going to lead to anything,” she said in an interview in May about her thinking in 2001. “I just didn’t see it.”

Nearly seven tumultuous years later, Ms. Rice, as secretary of state, has led the Bush administration to a startling turnaround and is now thrusting the United States as forcefully as Mr. Clinton once did into the role of mediator between the Israelis and Palestinians. The culmination of her efforts occurs this week in Annapolis, Md., as Mr. Bush, Prime Minister Ehud Olmert of Israel and Mahmoud Abbas, the Palestinian president, meet to set the outlines of a final peace agreement before the end of Mr. Bush’s term.

For Ms. Rice, Annapolis reflects her evolution from passive participant to activist diplomat who has been willing to break with Mr. Cheney and other conservatives skeptical of an American diplomatic role in the Middle East. Mr. Cheney argued with Ms. Rice against a pivotal Middle East speech that Mr. Bush gave in 2002 in the Rose Garden, fought her on a host of other issues, including Iran and North Korea, and today surrounds himself with senior advisers dubious about the Annapolis meeting.

Many other Middle East experts remain unconvinced as well, particularly since the failure so far of the Israelis and Palestinians to agree on a joint statement to come out of the 40-nation conference has forced Ms. Rice to recast Annapolis as the start rather than the end of negotiations. Critics say she is organizing little more than an elaborate photo opportunity.

“This administration has too often engaged in stagecraft, not statecraft,” said Dennis Ross, who was Middle East envoy for Mr. Clinton and the first President George Bush. “One of the reasons there’s so much skepticism from people in the region is that they were led to believe that this was going to be a breakthrough.”

Ms. Rice’s thinking on the Middle East changed for several reasons, her aides said. She has been under increasing pressure to get involved in the peace negotiations from European and Arab leaders whose support she needs for the campaign of diplomatic and economic pressures on Iran. She considers it equally important, her aides said, to shore up the moderate leadership of Mr. Abbas, who is facing a sharp internal challenge from the more militant Hamas faction.

Not least, Ms. Rice’s supporters say, she is determined to fashion a legacy in the Middle East that extends beyond the war in Iraq.

Ms. Rice was able to engineer the administration’s shift in large part because of her extraordinarily close relationship with the president — Mr. Bush “loved Condi,” said Andrew H. Card Jr., the former White House chief of staff — and her ability to move him at critical moments. Mr. Bush, Ms. Rice insisted, is also fully committed to the Annapolis meeting.

“The president has wanted to see this happen,” Ms. Rice said in a recent interview. “We have discussions about how to do it — is the time right for this or is the time right for that? But this is the president’s issue as much as it’s mine.”

Ms. Rice began her journey as a voice of caution in the first big Middle East crisis the White House faced, in the spring of 2002, when a Palestinian suicide bomber blew himself up at a large Passover meal in an Israeli beach resort hotel. The militant group Hamas took responsibility, and Israel’s leaders, reacting with fury, sent troops and tanks to storm the Ramallah compound of Yasir Arafat, the Palestinian leader.

Mr. Bush responded by dispatching Mr. Powell to the region, even though both believed that there was little the United States could do. “The president said, ‘You’ve got to go, it’s going to be ugly, you’re going to get beaten up, but you’ve got a lot of fire wall to burn up,’” Mr. Powell recalled.

Ms. Rice, whose first trip to Israel was in 2000, stayed back in Washington to monitor and rein in Mr. Powell. She was the messenger for Mr. Bush, who had adopted his hands-off policy in Middle East negotiations not only because of Mr. Clinton but because he was reluctant to make too many demands on Israel at that point in his term. So as Mr. Powell traveled from fruitless meetings with Ariel Sharon, then the prime minister, in Jerusalem and Mr. Arafat in Ramallah, Ms. Rice was constantly on the telephone admonishing Mr. Powell to slow down to avoid putting too much pressure on Mr. Sharon, Mr. Powell recalled.

“She was conveying whatever angst existed in the White House that day,” Mr. Powell said. “It was cautionary and wanting to know what I was doing so she could report it to the president.”

By the end of the trip, Ms. Rice even rejected Mr. Powell’s idea of a peace conference in the region, but Mr. Powell dug in. “I finally told her, late at night, ‘You may not like it, but I’m the one who’s here, and I’ve got to say something,’” Mr. Powell said he told Ms. Rice. He announced the conference before returning to Washington, but without support from the White House, the idea was dead.

The Bush administration might have continued with bursts of attention followed by drift had it not been for the looming war in Iraq. By June 2002, Mr. Bush and Ms. Rice realized that before the Europeans and Arabs would support an American-led invasion, the administration would have to prove that it cared about more in the Middle East than the security of Israel.

Mr. Bush and Ms. Rice began to engage in a major rethinking. The result was a speech, a major departure in American policy, that called for Palestinian elections and demanded the ouster of Mr. Arafat before the United States would support a Palestinian state. Ms. Rice saw it as the beginning of a notion that one day there could be a democratic Arab Middle East, but Mr. Rumsfeld and Mr. Cheney, who were strongly opposed to anything that might require Israel to accept a Palestinian state that could become a source for terrorism on its border, objected.

At a National Security Council meeting a few days before the speech, Mr. Cheney spoke up. “There was just a sense of was the president inserting himself in something that he didn’t have an answer for, and that was possibly going to make things worse or certainly not make them better?” Ms. Rice said, recalling the nature of Mr. Cheney’s doubts. Mr. Rumsfeld eventually agreed with the speech, but the vice president was still opposed on the day that Mr. Bush delivered it, June 24, 2002.

“I think he just thought the president shouldn’t be giving a speech on the Middle East, which kind of implied that if something happened, we might re-engage,” Ms. Rice said. Mr. Cheney declined to comment on Ms. Rice’s remarks.

Over the next year, the peace efforts languished as Ms. Rice and Mr. Bush focused on the coming invasion of Iraq. When Israeli tanks and troops surrounded Mr. Arafat’s compound again in September 2002, this time in response to back-to-back suicide bombings, Ms. Rice viewed the siege as damaging to the administration’s campaign to enlist support in the Arab world for the war in Iraq. In a White House meeting with Dov Weissglas, then a senior adviser to Mr. Sharon, the Israeli prime minister, Ms. Rice demanded, successfully, that the Israelis withdraw.

“She said in her way, politely but very firmly, that the United States was trying to put together the coalition prior to the invasion of Iraq, and our operation at that time was very disturbing,” Mr. Weissglas said in a recent interview.

It was not until the eve of the war in March 2003, and then only under pressure from Tony Blair, the British prime minister, that the White House finally endorsed the “road map,” a peace plan of incremental steps that was to lead to a Palestinian state in three years. Mr. Bush said he was adopting the plan because the Palestinians had slated Mr. Abbas to take the job of prime minister and negotiate with Israel.

By the spring of 2004, when Mr. Bush agreed to support a plan by Mr. Sharon to withdraw Israeli settlers and forces from Gaza, Mr. Sharon asked for something more that set off a huge fight within the administration: American recognition that Palestinian refugees and their descendants who had fled in the 1940s would have a right of return to a new Palestinian state, but not to Israel itself.

Ms. Rice agreed that allowing Palestinians to return to Israel would overwhelm the Jewish population and effectively obliterate Israel’s identity as a Jewish state. Mr. Cheney and his allies supported Mr. Sharon’s request, but the State Department had always taken the position that the issue — with the final borders of a Palestinian state and how Jerusalem might be shared by the two sides — should be decided through negotiations, not by fiat from Washington.

Aware of the debate within the Bush administration, Tzipi Livni, now the Israeli foreign minister but then the minister for immigrant absorption, went to plead her case to Ms. Rice in Washington. “I had the opportunity to convince Rice,” Ms. Livni said in an interview with The New York Times earlier this year.

Ms. Rice said she understood the issue was “very, very core” to Ms. Livni, and acknowledged that Ms. Livni’s appeal “was taken into account in the president’s words” when Mr. Bush made a pivotal announcement, in April 2004, that any “just, fair and realistic framework” for Israel would mean that Palestinians would have to settle in their own state — an enormous benefit to Mr. Sharon.

When Ms. Rice became secretary of state in the second term, she told Mr. Bush in a long conversation at Camp David the weekend after the 2004 election that her priority would have to be progress in the Middle East. It was a turning point in more ways than one; Mr. Arafat died a few days later. Although Ms. Rice said in an interview that she had set no conditions when she took the job, her aides said that she had known that her relationship with the president would give her far greater influence to push an agenda, including peacemaking in the Middle East, than Mr. Powell’s.

Accordingly, Ms. Rice spent much of 2005 working on the Gaza withdrawal that she thought would contribute to stability. Instead, it was seen as so emboldening the radicals that in early 2006 Hamas won a landslide victory in Palestinian elections over Mr. Abbas and his governing party, Fatah.

Ms. Rice, who had heralded the election as a symbol of the new stirrings of democracy in the Middle East, was so blindsided by the victory that she was startled when she saw a crawl of words on her television screen while exercising on her elliptical trainer the morning after the election: “In wake of Hamas victory, Palestinian cabinet resigns.”

“I thought, ‘Well, that’s not right,’” Ms. Rice recalled. When the crawl continued, she got off the elliptical trainer and called the State Department.

“I said, ‘What happened in the Palestinian elections?’” Ms. Rice recalled. “And they said, ‘Oh, Hamas won.’ And I thought, ‘Oh my goodness, Hamas won?’”

Ms. Rice’s credibility was further damaged when she delayed calling for a cease-fire as Israel plunged into a two-front war in Lebanon and Gaza that summer. By the end of 2006, with the peace efforts in shambles and the administration’s time running out, Ms. Rice began to pick up the pieces.

Over Christmas, she took home reports written by the State Department historian on previous American efforts toward a peace agreement in the Middle East, and met alone in her Watergate apartment with Ms. Livni. There they worked out an ambitious plan to get Mr. Olmert to meet with Mr. Abbas, not on the incremental steps of the road map, but on the big “final status” issues of a Palestinian state.

Since then, Ms. Rice has made eight trips to the region, and her supporters say she remains determined against the odds. “She knows very well if she doesn’t do anything, she will be Iraq,” a European diplomat and a friend of hers said.

Mr. Weissglas had another interpretation. “I don’t think she’s led by the desire to get a Nobel Prize for Peace,” he said. “But I think she truly believes in the last five years conditions have changed on both sides that enable now a step toward a final resolution.”