US President George W Bush has acknowledged for the first time that he made a "miscalculation" of what conditions would be in post-war Iraq.
The US is "adjusting" to present conditions in Iraq, said Mr Bush
Mr Bush told The New York Times that the error was by by-product of a "swift victory" in the initial conflict.
Saddam Hussein's military disappeared into cities, enabling them to mount a rebellion against US troops much faster than Washington anticipated, he said.
Mr Bush also told the newspaper John Kerry had not lied over his war record.
On Iraq, Mr Bush said the US's strategy had been "flexible enough" to respond to the long-running insurgency, and said that even now "we're adjusting to our conditions" in places such as Najaf, where a stand-off has just ended between US and Iraqi troops and Shia militants.
But Mr Bush declined to enter into discussion with the newspaper on further mistakes in Iraq.
He said, just as his father has done, that he would resist going "on the couch" to rethink decisions.
Asked by the USA Today, in a separate interview, how the death toll - now approaching 1,000 US military personnel - would affect his election chances, he answered: "The president has to make hard decisions.
"My job is to confront problems not pass them on. And the American people have seen me make the hardest of decisions. That's just going to have to be a part of their decision-making process."
On his opponent John Kerry, he declined to condemn the television advertisement paid for by a veterans group alleging that the Democrat presidential candidate came by his medals dishonestly.
But he stressed too that he was a victim of the same type of political interest groups - called 527 committees after the section of the tax code which governs this type of organisation - which are attacking Mr Kerry.
"I understand how Senator Kerry feels - I've been attacked by 527s too," he said.
He added that he had spoken earlier to Senator John McCain and had agreed to join him in a lawsuit against the Federal Election Commission to ban the groups.
The war records of President Bush and Mr Kerry have become a key issue in the campaign.
Pyongyang and Tehran
On the environment, Mr Bush appeared unfamiliar with an administration report delivered to Congress this week which suggested that carbon dioxide emissions were the only likely explanation for global warming over the last 30 years, said the newspaper.
Mr Bush in the past has said there are uncertainties in understanding the causes of global warming.
Asked why the administration had changed its mind on the causes of global warming, Mr Bush replied: "Ah, we did? I don't think so."
On North Korea and Iran, he said he would not be rushed into setting deadlines for the countries to disarm.
The newspaper said in the past Mr Bush has said he would not "tolerate" nuclear capability in either nation, but would not define what he meant by "tolerate".
"I'm confident that over time this will work - I certainly hope it does," he said of the ongoing diplomacy with the two nations.