Defense Secretary Richard B. Cheney fired Air Force Chief of Staff Gen. Michael J. Dugan yesterday for his public remarks on U.S. contingency plans for war with Iraq, including massive air raids against Baghdad that would target Iraqi leader Saddam Hussein and his family.

Cheney told reporters that Dugan, 53, "showed poor judgment at a sensitive time." "This was not a pleasant action for me to take, but under the circumstances, I felt it was a necessary one," he said. While the White House said President Bush "concurred" in the removal of Dugan, Cheney said both the idea for the dismissal and the final decision were his.

In a statement distributed by the Air Force, Dugan, a 32-year veteran and former fighter pilot who became Air Force chief only three months ago, said, "I sincerely regret any embarrassment that my comments may have caused the administration." He said he was presenting his "personal views."

Cheney said that Dugan's comments, made to reporters while on a tour of U.S. forces deployed in the Persian Gulf and reported Sunday in The Washington Post and the Los Angeles Times, had shown "lack of judgment" in disclosing "operational details" and in addressing "decisions that may or may not be made by the president in the future."

Among the comments that apparently angered Cheney and other officials was Dugan's assertion that the Bush administration had accepted the advice of Israeli sources that "the best way to hurt Saddam" is to target him and his family.

The administration is particularly sensitive about any mention of cooperation or consultation with Israel on the current gulf crisis, in which Washington has established close alliances with Arab governments in the region.

At the same time, Cheney noted in explaining his decision that the specific targeting of Saddam might violate a U.S. presidential order barring assassination of foreign leaders. Similar concerns were raised in Congress and elsewhere following the 1986 U.S. bombing attack against Libya, when the Reagan administration denied it had directly targeted Libyan leader Moammar Gadhafi in a raid that damaged his personal compound and killed an adopted daughter.

Cheney also accused Dugan of revealing classified information "about the size and disposition of U.S. forces" and raised concerns about Dugan's assertion that the Iraqi air force has only limited capability and that the U.S. Air Force would play the most important role in any attack on Iraq.

The highly unusual move made Dugan one of only a handful of senior U.S. military officers cashiered by civilian leaders since World War II. Dugan could not be reached yesterday for comment.

Cheney cited the "extreme delicacy" of the largest U.S. military deployment since the Vietnam War, telling Pentagon reporters Dugan's statements were not as "discreet and tactful" as they should have been. Neither he nor White House national security adviser Brent Scowcroft, who expressed displeasure separately after the remarks were published on Sunday, challenged the substance of Dugan's comments about military plans.

Scowcroft bluntly told CBS's "Face the Nation" Sunday after the newspaper articles appeared that "General Dugan is not in the chain of command and he does not speak for the administration."

Officials said Scowcroft was referring to the established procedure in which military orders are passed from Bush to Cheney, and then to the tactical commander in the field.

Scowcroft emphasized the defensive mission of U.S. forces. "We have contingency planning for anything that might happen. That's only prudent," Scowcroft said. "The president has described our strategy, which is to defend Saudi Arabia, to impose economic sanctions, and to force Saddam Hussein to withdraw from Kuwait."

Cheney said yesterday that Air Force Gen. John Michael Loh, the vice chief of staff, will act in Dugan's place until the president formally nominates Gen. Merrill A. McPeak, commander of the Pacific Air Forces, as a replacement.

Throughout the U.S. gulf deployment, military officials have been uncharacteristically open in discussing their plans and the situation on the ground, offering comments for publication as part of what White House and Pentagon sources have described as a deliberate war of nerves with the Iraqi leader. Gen. H. Norman Schwarzkopf, commander of U.S. forces in Saudi Arabia, and others have described in some detail how U.S. forces would respond to Iraqi aggression and conflict. Military officials have said repeatedly that the United States would respond rapidly to any attack with a massive air strike at specific Iraqi targets, especially in the period before U.S. ground forces are fully deployed.

"Should there be a provocation," Cheney said last week, "it would be appropriate . . . to hold at risk targets -- assets, if you will -- that Saddam Hussein holds dear, and specifically, assets inside Iraq."

But administration officials said yesterday that these remarks were less detailed and much less politically sensitive than those made by Dugan, who was made Air Force chief of staff July 1 and has endeavored to provide more information and access to reporters than his recent predecessors.

The initial reaction on Capitol Hill was positive. Sen. Sam Nunn (D-Ga.), chairman of the Senate Armed Services Committee, and Sen. John W. Warner (Va.), the panel's senior Republican, issued a joint statement calling the firing "justified." They said Dugan's statements were "inappropriate." House Armed Services Committee Chairman Les Aspin (D-Wis.) echoed that sentiment in a statement.

Asked why Bush would be angered by what appeared to be a deliberate message to Saddam Hussein about the use of American military might, a senior U.S. official said, "When a message . . . is being sent on behalf of the commander-in-chief, he ought to know about it."

Asked whether Dugan's revelations and their aftermath had damaged U.S. efforts in the gulf and attempts to win international support for sanctions against Iraq, Bush told regional reporters, "I don't think we can possibly assess that at this juncture to give you a real answer." He added that he was not concerned that the revelations caused any increased danger to U.S. troops.

The legality and morality of attacks against foreign leaders have been vexing issues in U.S. policy debates since 1981, when President Ronald Reagan signed an executive order barring any person employed by or acting on behalf of the government from engaging in, "or conspiring to engage in, assassination."

When an Air Force F-111 aircraft bombed Gadhafi's personal compound in 1986, U.S. officials initially denied trying to kill him. But officials acknowledged later that their uncertainty over Gadhafi's exact whereabouts at the time of the attack left open that possibility, and some said they had hoped it would occur.

Last year, the Bush administration announced that it had reinterpreted the presidential order to allow Central Intelligence Agency assistance in foreign coup attempts that result in the death of a foreign leader as long as the death does not occur as the result of an explicit goal.

Cheney used two different formulations in his public comments yesterday about Dugan's statement that the United States planned to target Saddam and his top aides. Appearing before a group of regional journalists, Cheney said, "That's a violation of the executive order." He told Pentagon reporters later, however, that "I think it is potentially a violation."

A senior Pentagon official explained later that "the second statement is the definitive one."

Asked why Dugan had received such a swift and severe rebuke for his remarks, a senior U.S. official speaking on condition that he not be identified said "it was especially egregious" to cite Israeli advice in discussing targeting plans, as if "for some reason, we base our targets on what the Israelis want us to do."

Several officials also expressed concern over Dugan's disclosure that Israel had provided air-to-ground Have Nap missiles for U.S. B-52 bombers based in Diego Garcia, which might be used in an attack on Iraq.

Officials noted that Dugan, in an Aug. 1 speech, had encouraged senior Air Force officials to be more open with reporters, saying, "I think that the leaders . . . need to be upfront, they need to be the guys on point, and they need to take the gaff that goes with it and the flack that goes with it."

Staff writers Ann Devroy and Helen Dewar contributed to this report.