WASHINGTON -- The legal and political stakes are of the highest order, but the investigation into the disclosure of a covert CIA officer's identity is also just one skirmish in the continuing battle over the Bush administration's justification for the war in Iraq.

That fight has preoccupied the White House for more than three years, repeatedly threatening President Bush's credibility and political standing, and has now once again put the spotlight on Vice President Dick Cheney, who assumed a critical role in assembling and analyzing the evidence about Iraq's weapons programs.

The dispute over the rationale for the war has led to upheaval in the intelligence agencies, left Democrats divided about how aggressively to break with the White House over Iraq and exposed deep rifts within the administration and among Republicans.

The combatants' intensity was underscored this week in a speech by Lawrence Wilkerson, the former chief of staff to Colin L. Powell while he was secretary of state.

Wilkerson complained of a ''cabal'' between Cheney and Defense Secretary Donald H. Rumsfeld that bypassed normal decision-making channels when it came to Iraq and other national security issues.

He described ''real dysfunctionality'' in the administration's foreign policy team and said that Powell's aides had thrown out ''whole reams of paper'' from the intelligence dossier developed by Cheney's staff for use in Powell's presentation of the case against Iraq to the United Nations in early 2003.

Cheney's focus on the threat from Iraq has put some of his aides, especially I. Lewis Libby Jr., his chief of staff, in the middle of an investigation by a special prosecutor into the leak of the CIA operative's name.

According to lawyers in the case, Libby remains under scrutiny in the investigation stemming from his effort to rebut criticism by Joseph C. Wilson IV, a former diplomat, that the administration had twisted intelligence about Iraq's nuclear program.

Libby has become emblematic of the broader Iraq debate, cast by supporters as a loyal aide working diligently to set the record straight, and by critics as someone working to smear or undermine the credibility of a politically potent opponent.

''The way in which the leak investigation is being pursued is becoming a symbol of who was right and who was wrong about the war,'' said Ivo H. Daalder, a senior fellow at the Brookings Institution who worked at the National Security Council during the Clinton administration.

The passions surrounding the investigation and the question of why the administration got it wrong about Iraq's weapons programs, other analysts agree, reflect the troubled course of the war and the divisions over whether it was necessary or was a diversion from the effort to combat Islamic extremism.

The administration has acknowledged the failures of pre-war intelligence, though its supporters have pointed out that many Democrats, including former President Bill Clinton, and the intelligence services of other countries were also convinced that Saddam Hussein had caches of banned weapons.

But the White House's insistence that there were many other compelling reasons for deposing Saddam Hussein have only inflamed critics of the war.

''There's a daisy chain that stems from the fact that no weapons of mass destruction have been found,'' said Richard N. Haass, president of the Council on Foreign Relations.

''Iraq was at core a war of choice, and extraordinarily expensive by every measure -- human life, impact on our military, dollars, diplomatically,'' said Haass, a former senior State Department official under President Bush.

''If this war was widely judged to have been necessary along the lines of Afghanistan after 9/11,'' Haass said, ''I don't believe you would have this controversy. If the war had gone extremely well, you wouldn't have this controversy.''

While the leak case has ensnared other officials, most prominently Karl Rove, Bush's senior adviser and deputy chief of staff, the special prosecutor, Patrick J. Fitzgerald, appears to have devoted much effort to understanding the role of Cheney's office and actions taken by Libby, who has twice testified before the grand jury.

In May and June 2003, Wilson began circulating his criticism of the administration's assertions that Iraq had been seeking nuclear material in Africa.

At that point, Libby showed an intense interest in Wilson's public statements and argued to colleagues that Wilson should be rebutted at every turn, a former administration official said, confirming an account on Friday in The Los Angeles Times.

Libby also sought to insulate Cheney from Wilson's critique, telling journalists that Wilson's trip to Africa to assess Iraq's intentions was orchestrated by the CIA.

Libby's involvement in assembling the case that Iraq's weapons constituted an urgent threat began well before the invasion.

In his 2004 book ''Plan of Attack,'' Bob Woodward of The Washington Post wrote that Powell had rejected Libby's draft as ''worse than ridiculous,'' which Wilkerson alluded to in his speech last week.

That episode added to tensions between Cheney's office and senior officials at the CIA, which had also dismissed as unwarranted claims by Cheney and others about close links between Iraq and al-Qaida.

Before the war, the CIA also issued intelligence assessments warning of potential obstacles to the stability of postwar Iraq, although the agency's capabilities have also been harshly criticized since the war, and it is now in the midst of upheaval set off by the creation of a new intelligence structure and the appointment of a new director, Porter J. Goss.

The wrangling over the U.N. speech exposed long-simmering suspicions by some administration officials about the reliability of the CIA's intelligence on Iraq.

A former intelligence official who previously worked with Libby said that his antipathy to the CIA dated back at least 15 years, to the first Bush administration, when he was working under Wolfowitz at the Defense Department.