But some things haven't changed a bit: the trademark smirk when he is amused, a squinty glare when he doesn't appreciate the question -- and a quick turn to humor when the conversation turns to "legacy," including the scars of Iraq or the cloud of Katrina.
"History will ultimately judge the decisions that were made for Iraq and I'm just not going to be around to see the final verdict," the two-term president told CNN in a wide-ranging interview.
On Thursday, every living president will be on hand for the dedication of the George W. Bush Presidential Center in Dallas. One, of course, will be his father, George Herbert Walker Bush; the other three, Democrats -- Presidents Jimmy Carter, Bill Clinton and Barack Obama. Photos: George W. Bush's life, legacy Photos: George W. Bush's life, legacy Photos: The George W. Bush Presidential Center Photos: The George W. Bush Presidential Center
The 43rd president said he has learned lessons from his predecessors about how to make a mark after leaving the White House.
"You learn that life doesn't end after you're president," Bush said. "In other words, you're going a hundred miles an hour and, and, in my case, we woke up in Crawford and now it's going zero. And so the challenge is how to live life to its fullest.
"In my case, I've chosen to do so outside the limelight. On the other hand, I am confident that when this chapter of our life is finished, that we'll both be able to say that we've advanced the cause of peace and freedom and -- and the human -- and helped improve the human condition."
In July, Bush visited Zambia and Botswana to promote a health initiative that focuses on cervical and breast cancer prevention and treatment. He also helped create the Clinton Bush Haiti Fund, which focuses on long-term economic reconstruction projects that create jobs and promote economic opportunity.
Laura Bush said her husband rarely itches to add his voice to the daily political debate. The former president said he knows the library dedication will re-stir the debate about his presidency, and he conceded the library is in part an effort by him and supporters to influence history's verdict.
But he predicted visitors would find it "more objective" than they might have imagined and he showed little interest in revisiting flash points like Iraq, Hurricane Katrina or the 2008 financial crisis. Or the scorn with which many look back at the Bush presidency.
"You know, I'm really not that concerned about why people did what during my presidency." Bush said. "I'm more concerned about being an effective person for the rest of my life.
"I know this, that Laura and I gave the presidency eight years of our life. We gave it our all. Made the best judgment calls I could. I didn't compromise my principles. And I'm a content man. And I am excited about what we're going to do here."
The library path is a quick reminder of how everything changed on a crisp September morning. One early exhibit is filled with children's books -- education reform was to be a major first term priority.
Then, the dress Laura Bush wore to a state dinner on September 6, 2001, for then-Mexican President Vicente Fox. Candidate Bush had promised a humble foreign policy, with a heavy focus on the Western Hemisphere.
One step past images of that festive dinner takes you into the horror and carnage of September 11, including a twisted beam from the second tower of the World Trade Center and the bullhorn the president used during his now iconic visit to the rubble at ground zero a few days after the attacks.
Given his heavy focus on terrorism as president, we began the conversation with his thoughts when he heard the news of the explosions at the Boston Marathon finish line.
"I was reminded that evil exists," Bush said. "And that there are people in the world who are willing to kill innocent people to advance a cause."
The Decision Points Theater is a centerpiece of the library tour. Visitors can relive big Bush administration policy debates, and read and listen to some of the advice given to the president at the time. Then they can pick a course of action.
Never known as one to second-guess himself, the former president conceded problems in administering the Iraq war but was adamant he believed history would embrace the decision to go to war.
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(Article courtesy of CNN.com)