Condoleezza Rice, who will be named as Colin L. Powell's replacement as early as today, has forged an extraordinarily close relationship with President Bush. But, paradoxically, many experts consider her one of the weakest national security advisers in recent history in terms of managing interagency conflicts.

Her appointment as secretary of state would be a first for a black woman, and it would mean an unquestioned Bush loyalist would be dispatched to run a critical department that the White House had come to view with suspicion.

But she will have to work hard to build bridges to State Department career officials, current and former officials said. Powell was considered a hero to the State Department bureaucracy because he won increases in funding and personnel, and many State Department officials are furious that the Bush White House frequently undercut Powell.

"State Department officials dislike her intensely because they love Powell and believe her staff demeaned the State Department," said one former State Department official who spoke on condition of anonymity because he frequently interacts with Rice.

Rice is a poor Alabama cotton farmer's granddaughter who became an accomplished classical pianist and ice skater and graduated from college at 19. She speaks Russian and served a two-year stint as the National Security Council's Soviet expert in the administration of President George H.W. Bush. She also was named, at age 38, provost of Stanford University, essentially the chief operating officer of a huge institution.

She was Bush's first tutor on foreign policy, during the 2000 campaign, and bonded with him over a common love of sports. She has frequently joked that her dream job is commissioner of the National Football League.

Her bond with Bush continued into the White House. Rice has spent countless hours at Bush's side -- in the White House, at Camp David and at his ranch in Crawford, Tex. -- forging a relationship that has transcended the statutory position of national security adviser.

David Rothkopf, who has written a forthcoming history of the National Security Council titled "Running the World," said that much of the success of a national security adviser is defined not by the adviser but by the president. He said Rice "could not be more effective" as a top staffer to Bush because of the closeness she has had with him.

But Rice's management of the interagency process has been lagging, according to Rothkopf and former and current officials. In part, this is because Rice not only had to manage two powerful Cabinet members with sharply different views -- Powell and Defense Secretary Donald H. Rumsfeld -- but also to deal with a player distinctive to the Bush administration: Vice President Cheney, who weighs in on every major foreign policy question.

Rothkopf said Bush undercut Rice in her running of the interagency process because he has allowed Cheney and Rumsfeld to operate outside the control of the NSC. "The president has to put his foot down and say, 'This has to stop,' " Rothkopf said, but Bush never did.

In an interview for Rothkopf's book, Rice, who turned 50 on Sunday, noted that she was "the baby" of the group, whereas Cheney, Powell and Rumsfeld had dealt with one another over decades.

But now, Rothkopf said, "her unique relationship with the president is going to enable her to counterbalance Rumsfeld if he stays -- or anyone else. Condi has a better chance of being balanced with these guys now than Colin Powell four years ago."

Despite her experience as Stanford's provost, her managerial skills were often called into question when running the NSC. According to Bob Woodward's book, "Plan of Attack," Deputy Secretary of State Richard L. Armitage privately complained to Rice that the interagency process was dysfunctional.

Throughout the first term, policies on such critical issues as dealing with North Korean and Iranian nuclear programs have remained mired in disagreement, and officials said Rice never seemed to drive the process to a resolution. Officials on both sides of the administration's debate over North Korea faulted Rice for failing to fashion a coherent approach to dismantling North Korea's nuclear program.

The Sept. 11 commission report was particularly tough on Rice, portraying her as failing to act on repeated warnings in the first part of 2001 about the likelihood of a major terrorist attack on the United States.

For example, it noted that on Jan. 25, 2001, a few days after Bush took office, Richard A. Clarke, who had been held over from the previous administration as the counterterrorism coordinator for the NSC, wrote to Rice stating that "We urgently need . . . a Principals level review on the al Qaeda network." The report noted that Rice did not respond directly to Clarke's memo, and no such meeting of principals, or top officials, was held on terrorism until Sept. 4, 2001, although they met frequently on other issues, such as the Middle East peace process, Russia and the Persian Gulf.

The report also detailed several more specific warnings from Clarke to Rice in the spring and summer of 2001:

* On March 23, he told Rice that he thought terrorists might attack the White House with a truck bomb and also that "he thought there were terrorist cells within the United States, including al Qaeda."

* On May 29, Clarke wrote to Rice and her deputy, Stephen J. Hadley, about possible assaults by a Palestinian associate of al Qaeda, adding that, "When these attacks occur, as they likely will, we will wonder what more we could have done to stop them."

* On June 25, Clarke informed Rice and Hadley that "six separate intelligence reports showed al Qaeda personnel warning of a pending attack," the report said.

* Three days later, he added that the pattern of al Qaeda activity indicating preparations for an attack "had reached a crescendo."

* On June 30, a briefing was given to top officials titled, "Bin Ladin Planning High-Profile Attacks."

The spike in reported al Qaeda activity ended in July, but senior intelligence analysts continued to be deeply concerned, the report noted, causing them to include in the Aug. 6 "President's Daily Brief" an article titled "Bin Ladin Determined to Strike in US."

The report's findings are likely to figure in Rice's confirmation hearings but not for Hadley, if he is tapped to succeed her, because national security adviser is an appointment that does not require Senate approval.

National security adviser Condoleezza Rice, shown attending this year's State of the Union address, has been one of President Bush's closest advisers but has struggled in a management role, officials say.