Defense Secretary Donald H. Rumsfeld (search), for years the most public face of the Bush administration's war on terrorism, has suddenly become scarce.

Burdened by the Iraq prisoner abuse (search) scandal and constrained by the presidential election campaign, the Pentagon chief who spearheaded the Afghanistan and Iraq wars has been relegated to a less visible role.

Once seemingly in danger of being fired over the prisoner abuse, Rumsfeld appears to have survived. Yet some wonder whether the White House might still conclude he is a political liability and prefer he leave this summer.

"Donald Rumsfeld has gone from being the most popular spokesperson for the Bush administration policies to something of a pariah," said Loren Thompson of the Lexington Institute, a think tank.

"Whereas before the White House was happy to see him speaking in public whenever he chose, now it kind of cringes for fear of what the results might be," Thompson added.

Since an April 27 news conference — one day before CBS News broadcast photographs of U.S. soldiers abusing Iraqis at the Abu Ghraib (search) prison — Rumsfeld has appeared in the Pentagon briefing room just twice, on May 4 and June 17. In April he had four Pentagon news conferences; in March he had three.

Larry Di Rita, the chief spokesman for Rumsfeld, said the change is not an indication the secretary has fallen out of favor with the White House.

Rather, it reflects the fact that when Iraq's sovereignty was restored June 28 and the Coalition Provisional Authority was disbanded, the Defense Department was no longer in charge of Iraq, the spokesman said.

Various U.S. public opinion polls show the defense secretary's popularity on the decline.

He was viewed favorably by two-thirds two years ago and almost as many at the start of the war in March 2003. By last September his favorable rating was just above 50 percent, and the most recent poll, in February, had it slipping about 10 points further.

The last time Rumsfeld held a Pentagon news conference, nearly a month ago, he was asked about his lower public profile.

"I've been very much involved," Rumsfeld retorted dismissively. Evidently armed in advance, he rattled off statistics on the number of his speeches, interviews and congressional appearances.

Rumsfeld has continued to travel abroad with regularity. He was in Turkey and Moldova in late June and he made a one-day trip to Iraq on May 13 to visit U.S. troops at the Abu Ghraib prison. In early June he visited Bangladesh and Singapore.

The only time he has fielded reporters' questions in Washington this month was at the State Department, where he and Secretary of State Colin Powell appeared briefly with Australian officials.

For a time after the Abu Ghraib scandal, it looked as though Rumsfeld might be forced out. On May 5, White House aides leaked word that President Bush had told Rumsfeld he was unhappy about not being told about the abuse sooner.

Two days later, during an appearance before the Senate Armed Services Committee, Rumsfeld apologized for the abusive conduct and said he accepted full responsibility.

Rumsfeld, who turned 72 this month, said he would not quit just to satisfy his political enemies but added that if he felt he could no longer be effective as defense secretary, "I'd resign in a minute."

William Nash, a senior fellow at the Council on Foreign Relations and a retired two-star Army general who commanded American peacekeeping forces in Bosnia, said the White House's political calculations will determine Rumsfeld's fate.

"Right now everything in this administration is being measured against whether or not it contributes to the re-election of the president in November," he said. "Obviously he's been a lightning rod and oh, by the way, he's also been wrong and that's never good" for Bush.

Nash suspects that Rumsfeld has yet to feel the full force of the Abu Ghraib abuse.

"I don't think there's any particular reason to believe that the Department of Defense is out of the woods on Abu Ghraib," he said.