Eight days before he was to hand power to President-elect Barack Obama, Bush defended his decisions on the Iraq war, the issue that will define his presidency like no other. There have been more than 4,000 U.S. deaths and thousands of Iraqis killed since the invasion and toppling of Saddam Hussein in 2003.

The 43rd president said "not finding weapons of mass destruction was a significant disappointment." The accusation that Saddam had and was pursuing such devastating weaponry was Bush's main initial justification for going to war.

And, Bush said, he had miscalculated when -- eager to report quick progress after U.S. troops ousted Saddam Hussein -- he made a victory speech in front of a "Mission Accomplished" banner draped across an aircraft carrier five years ago.

"In the battle of Iraq, the United States and our allies have prevailed," he declared triumphantly May 1, 2003, from the deck of the USS Abraham Lincoln off the coast of San Diego.

"Clearly putting `Mission Accomplished' on an aircraft carrier was a mistake," he said in Monday's news conference.

He also defended his decision in 2007 to send an additional 30,000 American troops to Iraq to knock down violence levels and stabilize life in the country.

"The question is, in the long run, will this democracy survive, and that's going to be a question for future presidents," he said.

Bush listed the handling of prisoners in Iraq's Abu Ghraib prison among the failures of his second term. Pictures emerged and were widely distributed showing U.S. soldiers abusing detainees in prison, an event that served to deepen Muslim animosity over the American invasion of Iraq.

Bush referred to the enormous weight Obama is about to experience, describing what it might feel like on Jan. 20 when, after taking the oath of office, he enters the Oval Office for the first time as president. "There'll be a moment when the responsibility of the president lands squarely on his shoulders," Bush said.

He also said he hoped the tone in Washington improves during the Obama administration, declaring "the rhetoric got out of control" during his presidency.

"I hope that if people disagree President Obama, they treat him with respect," Bush said.

He also defended the federal government's handling of the aftermath of Hurricane Katrina after it flattened a broad swath of the U.S. Gulf of Mexico coast.

"Don't tell me the federal response was slow when there were 30,000 people pulled off roofs right after the storm passed," Bush said in an animated accounting of his presidency.

He declared himself disappointed that Congress failed to move on foreign trade bills and warned against the United States turning inward during it's current economic slump.

"It would be a huge mistake if we become a protectionist nation," Bush said.

On other matters of foreign policy, Bush defended Israel's actions in Gaza while calling for both the Jewish state and Hamas to work to a sustainable cease-fire.

He also defended the administration's efforts to broker peace between the Israelis and Palestinians, declaring that he thought there would be a peace built on a two-state solution.

"I think we have advanced the process," the president said.

He took pains to wish Obama, who will become the 44th president Jan. 20, every success and congratulated the country for electing its first African-American president.

"I consider myself fortunate to have a front-row seat on what is going to be a historic moment for the nation. President Obama's election does speak volumes about how far this country has come in terms of racial relations," Bush said.

As for his legacy as he leaves what may be one of the most controversial periods in U.S. history, Bush compared his presidency to that of Abraham Lincoln, who led the country through its bloody Civil War.

"I never spent that much time worrying about the loud voices (of critics). I of course heard them but they did not affect my policies," Bush said, predicting Obama would be "disappointed by the rhetoric that grows up in Washington and warning him that he will be let down by people who he thought were friends.

Bush said he was leaving it to his successor to decide on asking Congress to release a second $350 billion flood of federal funds designed to avert a collapse of the U.S. financial system.

"He hasn't asked me to make a request yet," Bush told reporters in a wide-ranging final question-and-answer session in which he thanked them for their professionalism even when he did not like what they were reporting.

"I don't intend to make a request unless he specifically asks me to make it," Bush said during the 36-minute news conference.

The request to Congress for the remainder of the $700 billion bailout money was still expected to land in Congress as early as Monday to permit Obama's administration to have the ability to use it shortly after taking office. The rescue fund was passed on Capitol Hill in September as the U.S. economic slide gained speed.

Obama, meanwhile, is working with Capitol Hill leaders to sell his own recovery package that was expected to call for additional spending of as much as $800 billion to reverse the worst U.S. economic downturn since the 1930's Great Depression.