The White House staunchly defended its Iraq (search) policy Tuesday as new questions emerged about President Bush's prewar decisions and postwar planning:

An impending weapons report undercut the administration's main rationale for the war, and the former head of the American occupation said the United States had too few troops in Iraq after the invasion.

Four weeks before Election Day, Democrat John Kerry pounced on the acknowledgment by former Iraq administrator Paul Bremer (search) that the United States had "paid a big price" for insufficient troop levels.

Kerry said there was a "long list of mistakes" that the Bush administration had made in Iraq.

"I'm glad that Paul Bremer has finally admitted at least two of them," Kerry said, referring to postwar troop levels and a failure to contain chaos.

At a campaign stop in Tipton, Iowa, Kerry said the question for voters was whether Bush was "constitutionally incapable of acknowledging the truth" or was "just so stubborn."

In a rare day spent in Washington, Bush had no public appearances. Speechwriters polished an address that White House aides said would be a sweeping indictment of Kerry's Iraq policies, while Bush prepared for his second debate with Kerry on Friday.

Bremer last month, in a speech at DePauw University in Indiana, said he had raised within the Bush administration the issue of too few troops and "should have been even more insistent" when his advice was rejected.

White House spokesman Scott McClellan refused to say if Bremer had pleaded with Bush for more troops, saying, "We never get into reading out all the conversations they had."

Bush consulted military commanders — not his hand-picked Iraq administrator — for guidance on troop levels, McClellan said, adding, "The lessons from the past, including Vietnam, are that we shouldn't try to micromanage military decisions from Washington."

In an unusual public acknowledgment of internal dissent, Bush campaign spokesman Brian Jones said Bremer and the military brass had clashed on troop levels.

"Ambassador Bremer differed with the commanders in the field," Jones said. "That is his right, but the president has always said that he will listen to his commanders on the ground and give them the support they need for victory."

Kerry said he would listen to both military and civilian leaders if elected.

"Commander in chief means you have to make judgments that protect the troops and accomplish the mission," Kerry told reporters in Iowa. "I would listen to all of my advisers and make the best decision possible."

The White House, meanwhile, sought to put the brightest face possible on the final report by the American weapons inspector in Iraq, Charles Duelfer (search), due out Wednesday. In earlier drafts, Duelfer found Saddam had left signs he had idle weapons programs he someday hoped to revive, but that Saddam did not have stockpiles of weapons of mass destruction.

President Bush, Vice President Dick Cheney and other top administration officials said repeatedly before invading Iraq that Saddam did have such weapons and that they posed a threat not only to Iraq's neighbors but to the United States as well. The weapons were the main justification for the invasion.

Even before Duelfer's final report was issued, McClellan said it bolstered the White House's assertions on Iraq.

The report will conclude "that Saddam Hussein (search) had the intent and the capability, that he was pursuing an aggressive strategy to bring down the sanctions, the international sanctions, imposed by the United Nations through illegal financing procurement schemes," McClellan said. "The report will continue to show that he was a gathering threat that needed to be taken seriously, that it was a matter of time before he was going to begin pursuing those weapons of mass destruction," he said.

Separately, Defense Secretary Donald H. Rumsfeld ignited another brush fire Monday, saying he knew of no "strong, hard evidence" linking Al Qaeda (search) and Saddam Hussein. He later backed off the statement and said he was misunderstood.

McClellan ticked off a litany of what he said were links between Iraq and Al Qaeda. Both were "sworn enemies of the free world, including the United States," and both "celebrated the Sept. 11 attacks on America," he said.

"There are clearly ties between Saddam Hussein's regime and Al Qaeda," McClellan said. "We know there were senior-level contacts between the regime and Al Qaeda — the 9/11 commission documented that," McClellan said.

In fact, the Sept. 11 commission (search) report said that while there were "friendly contacts" between Iraq and Al Qaeda and a common hatred of the United States, none "ever developed into a collaborative relationship."

In a reflection of the political significance of Iraq, the White House changed gears on Bush's Wednesday speech, which originally was planned as an address on health care. Now the speech in Wilkes-Barre, Pa., will focus on the war, as well as the economy.

People remain about evenly split on Bush's handling of Iraq, polls suggest. But almost six in 10 say they do not think Bush has a clear plan for successfully resolving the Iraq situation. The same number say Kerry does not either.