President George Bush conceded yesterday America had "a security issue in Iraq" as polls revealed public opinion growing increasingly sceptical about the presence and purpose of US troops in the Gulf.
With the number of American casualties still rising, two months after he declared victory from the deck of the USS Abraham Lincoln, the president admitted: "There's no question we've got a security issue in Iraq. We're going to have to deal with it person-by-person. We're going to have to remain tough."
Mr Bush's comments, a marked contrast to the "bring them on" stance of last week, have been prompted by a growing uncertainty about the role of American troops in Iraq among the public and the political establishment.
"We have the world's best-trained soldiers serving as policemen in what seems to be a shooting gallery," Senator Edward Kennedy told the defence secretary, Donald Rumsfeld, during a Senate armed forces committee hearing on Wednesday. "The lack of a coherent plan is hindering our efforts at internationalisation and aggravating the strain on our troops."
Mr Rumsfeld said there were no definite plans to remove the 145,000 ground troops, but that numbers might be increased. "It seems to me that we have to be prepared to increase our army ... and we have to make that decision soon," he said.
After persistent questioning by a Democratic senator, Mr Rumsfeld's team telephoned the Pentagon during a break in the hearing, and later revealed that the estimated military cost of the operations had risen from $2bn (£1.2bn) a month to $3.9bn.
General Tommy Franks, the former chief of the US central command, told the committee that continued Iraqi resistance meant troops would not be reduced "for the foreseeable future".
"I anticipate we'll be involved in Iraq in the future," he said. "Whether that means two years or four years, I don't know."
"We did anticipate a level of violence," Gen Franks said. "I can't tell you whether we anticipated it would be ... at the level we see right now."
Meanwhile questions continue to be raised over the accuracy of the intelligence used in the case for war, particularly the claim made by Mr Bush that Iraq had attempted to buy uranium from Niger.
The administration, which is under less pressure on this issue than the British government, has already admitted that its intelligence was faulty. But questions remain over how such an error made it into the president's state of the union address in January.
The concerns raised at the armed services committee during a four-hour hearing on Capitol Hill in many ways mirrored those of the US public.
"The problem here is that Americans are unsure about the future of our involvement in Iraq," the Republican senator John McCain told Mr Rumsfeld, describing the mood as "not disaffection, not anger, but unease".
A poll released by the Pew Research Centre this week shows that only 23% of Americans now believe the military effort in Iraq is going well, compared with 61% in April. The number of those who believe that military efforts are going badly has risen dramatically from 3% early on in the war to 21%. Despite this, 67% think that going into Iraq was the right decision.
Tensions run especially high at military bases where anxious families await the return of troops. Last week a colonel had to be escorted from a meeting with around 800 angry wives of servicemen at a base in Fort Stewart, Georgia.