Every living US president will join an unrepentant George W. Bush Thursday at the dedication of his new library, which seeks to shore up the ex-commander-in-chief's questionable place in history.
Democratic President Barack Obama will lead tributes to his Republican predecessor, who says he is "comfortable" with his decision to invade Iraq in 2003 and content to let history deliver its verdict on his White House.
The new 226,000 square foot building on the campus of Southern Methodist University in Dallas includes an archive of Bush's presidential papers, a museum stuffed with artifacts of his two terms and a policy institute.
As well as Obama, Bush will host his father, former president George H.W. Bush, and Democrats Jimmy Carter and Bill Clinton, and former secretary of state Hillary Clinton, who is already stirring 2016 speculation.
Former world leaders who were closest to Bush during his terror-seared first term, the march to war with Iraq and the months of recrimination afterwards were also in Dallas to honor their former comrade-in-arms.
Former British prime minister Tony Blair and his wife Cherie, former Australian prime minister John Howard, who was in Washington on September 11, 2001, and ex-Italian prime minister Silvio Berlusconi were on the guest list.
Other guests of honor include Israel's Ehud Olmert, Spain's Jose Maria Aznar and former South Korean president Lee Myung-Bak.
Obama based his 2008 election campaign on a repudiation of Bush, claiming the former president stained the US image abroad with the Iraq war and anti-terror tactics and presided over a disastrous economic crash.
But aides say he also shares a bond with the man who was president from 2001 to 2009, shared only by those who have faced the demands and trials of the Oval Office.
The president signaled Wednesday that in keeping with the dignity of the office they both shared and the gravity of the ceremony, that he would deliver a message of conciliation at the dedication event.
"One of the things I will insist upon is whatever our political differences, President Bush loves this country and loves its people," Obama said at a Democratic Party fundraiser.
In a series of interviews to pave the way for the opening of the library, financed by private benefactors, Bush made clear that he is not prone to second guessing in his retirement, in which he has kept out of the public eye.
Asked by ABC News whether he had any second thoughts about the 2003 invasion of Iraq, which is convulsed in a new wave of violence, Bush said: "I am comfortable in the decision-making process."
"I think the removal of Saddam Hussein was the right decision for not only our own security but for giving people a chance to live in a free society," Bush said.
"But history will ultimately decide that, and I won't be around to see it.
"As far as I'm concerned, the debate is over. I mean, I did what I did."
The US invasion swiftly toppled Saddam Hussein but the mismanaged aftermath of the war led to US forces becoming embroiled in a prolonged insurgency.
And the weapons of mass destruction which were the spur for the war were never found.
Memories of the September 11 attacks, which gave life to Bush's global war on terror, dominate the Bush museum, from a steel beam twisted in the inferno of the World Trade Center, to footage of the twin towers collapsing in ash clouds.
The library's story is of a president who thought he was going be occupied with domestic policy only to find himself defending the homeland from Al-Qaeda.
Bush left office in 2009 as one of the most unpopular presidents in recent history, with a Gallup approval rating of just 34 percent.
His absence from the scene seems to have improved his image slightly: in a CNN/ORC poll Wednesday, 42 percent said Bush's presidency was a success.
The centerpiece of the Bush library is an interactive exhibit known as "Decision Points Theater" which asks visitors to decide what they would have done on issues like Iraq, Hurricane Katrina in 2005 and the financial crisis.
The ex-president then pops up on a screen to justify the steps he actually did take.