Over the past year, Vice President Cheney has waged an intense and largely unpublicized campaign to stop Congress, the Pentagon and the State Department from imposing more restrictive rules on the handling of terrorist suspects, according to defense, state, intelligence and congressional officials.

Last winter, when Sen. John D. Rockefeller IV (D-W.Va.), vice chairman of the Senate Select Committee on Intelligence, began pushing to have the full committee briefed on the CIA's interrogation practices, Cheney called him to the White House to urge that he drop the matter, said three U.S. officials.

Vice President Cheney has fought restrictions on handling of terrorism suspects, rules favored by other administration officials and senators.

In recent months, Cheney has been the force against adding safeguards to the Defense Department's rules on treatment of military prisoners, putting him at odds with Secretary of State Condoleezza Rice and acting Deputy Secretary of Defense Gordon R. England. On a trip to Canada last month, Rice interrupted a packed itinerary to hold a secure video-teleconference with Cheney on detainee policy to make sure no decisions were made without her input.

Just last week, Cheney showed up at a Republican senatorial luncheon to lobby lawmakers for a CIA exemption to an amendment by Sen. John McCain (R-Ariz.) that would ban torture and inhumane treatment of prisoners. The exemption would cover the CIA's covert "black sites" in several Eastern European democracies and other countries where key al Qaeda captives are being kept.

Cheney spokesman Steve Schmidt declined to comment on the vice president's interventions or to elaborate on his positions. "The vice president's views are certainly reflected in the administration's policy," he said.

Increasingly, however, Cheney's positions are being opposed by other administration officials, including Cabinet members, political appointees and Republican lawmakers who once stood firmly behind the administration on all matters concerning terrorism.

Personnel changes in President Bush's second term have added to the isolation of Cheney, who previously had been able to prevail in part because other key parties to the debate -- including Attorney General Alberto R. Gonzales and White House counsel Harriet Miers -- continued to sit on the fence.

But in a reflection of how many within the administration now favor changing the rules, Elliot Abrams, traditionally one of the most hawkish voices in internal debates, is among the most persistent advocates of changing detainee policy in his role as the deputy national security adviser for democracy, according to officials familiar with his role.

At the same time Rice has emerged as an advocate for changing the rules to "get out of the detainee mess," said one senior U.S. official familiar with discussions. Her top advisers, along with their Pentagon counterparts, are working on a package of proposals designed to address all controversial detainee issues at once, instead of dealing with them on a piecemeal basis.

Cheney's camp is a "shrinking island," said one State Department official who, like other administration officials quoted in this article, asked not to be identified because public dissent is strongly discouraged by the White House.

A fundamental question lies at the heart of these disagreements: Four years into the fight, what is the most effective way to wage the campaign against terrorism?

Cheney's camp says the United States does not torture captives, but believes the president needs nearly unfettered power to deal with terrorists to protect Americans. To preserve the president's flexibility, any measure that might impose constraints should be resisted. That is why the administration has recoiled from embracing the language of treaties such as the U.N. Convention Against Torture, which Cheney's aides find vague and open-ended.

On the other side of the debate are those who believe that unconventional measures -- harsh interrogation tactics, prisoner abuse and the "ghosting" and covert detention of CIA-held prisoners -- have so damaged world support for the U.S.-led counterterrorism campaign that they have hurt the U.S. cause. Also, they argue, these measures have tainted core American values such as human rights and the rule of law.

"The debate in the world has become about whether the U.S. complies with its legal obligations. We need to regain the moral high ground," said one senior administration official familiar with internal deliberations on the issue, adding that Rice believes current policy is "hurting the president's agenda and her agenda."

McCain's amendment would limit the military's interrogation and detention tactics to those described in the Army Field Manual, and it would prohibit all U.S. government employees from using cruel, inhuman or degrading treatment.

Cheney pushed hard to have the entire amendment defeated. He twice held meetings with key lawmakers to lobby against the measure, once traveling to Capitol Hill in July, to button-hole Sens. John W. Warner (R-Va.), McCain and Lindsey O. Graham (R-S.C.).

When that tack did not work -- 90 senators supported the measure -- Cheney handed McCain language that would exempt the CIA. Despite Cheney's concerns, Graham said he has not heard any concerns from the CIA suggesting it needs an exemption from the McCain amendment. The CIA declined to comment.

"It shows that we have a philosophical difference here," said Graham, a member of the Senate Armed Services Committee. "The vice president believes in certain circumstances the government can't be bound by the language McCain is pushing. I believe that out of bounds of that language, we do harm to the U.S. image. It doesn't mean he's bad or I'm good; it just means we see it differently."

Cheney and the White House also oppose the language of a separate Defense Department directive, first reported by the New York Times, limiting detainee interrogations. The ongoing internal debate has stalled publication of the directive.

"This is the first issue we've gone to the trenches on," said a senior State Department official.

On the issue of the CIA's interrogation and detention practices, this spring Cheney requested the CIA brief him on the matter. "Cheney's strategy seems to be to stop the broader movement to get an independent commission on interrogation practices and the McCain amendment," said one intelligence official.

Beside personal pressure from the vice president, Cheney's staff is also engaged in resisting a policy change. Tactics included "trying to have meetings canceled ... to at least slow things down or gum up the works" or trying to conduct meetings on the subject without other key Cabinet members, one administration official said. The official said some internal memos and e-mail from the National Security Council staff to the national security adviser were automatically forwarded to the vice president's office -- in some cases without the knowledge of the authors.

For that reason, Rice "wanted to be in all meetings," said a senior State Department official.

Cheney's chief aide in this bureaucratic war of wills is David S. Addington, who was his chief counsel until last week when he replaced I. Lewis "Scooter" Libby as the vice president's chief of staff.

Addington exerted influence on many of the most significant policy decisions after Sept. 11, 2001. He helped write the position on torture taken by the Justice Department's Office of Legal Counsel, a stance rescinded after it became public, and he helped pick Guantanamo Bay, Cuba, as the location beyond the reach of U.S. law for holding suspected terrorists.

When Addington learned that the draft Pentagon directive included language from Article 3 of the Geneva Conventions, which prohibits torture and cruel treatment, including "humiliating and degrading treatment," he summoned the Pentagon official in charge of the detainee issue to brief him.

During a tense meeting at his office in the Eisenhower Executive Office Building, Addington was strident, said officials with knowledge of the encounter, and chastised Deputy Assistant Secretary Matthew C. Waxman for including what he regarded as vague and unhelpful language from Article 3 in the directive.

On Tuesday, Cheney, who often attends the GOP senators' weekly luncheons without addressing the lawmakers, made "an impassioned plea" to reject McCain's amendment, said a senatorial aide who was briefed on the meeting and spoke on the condition of anonymity because of its closed nature. After Senate aides were ordered out of the Mansfield Room, just steps from the Senate chamber, Cheney said that aggressive interrogations of detainees such as Khalid Sheik Mohammed had yielded useful information, and that the option to treat prisoners harshly must not be taken from interrogators.

McCain then rebutted Cheney's comments, the aide said, telling his colleagues that the image of the United States using torture "is killing us around the world." At least one other senator, Ted Stevens (R-Alaska), supported Cheney, as he has in public, the aide said.

Staff writers Charles Babington and Josh White contributed to this report.

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