He squeaked into office by the narrowest of margins -- a Texas governor from outside the Washington orbit who promised a new brand of politics to heal a divided nation.
Yet George W. Bush never governed like a president who harbored uncertainties or self-doubt about his capacity to lead. He never lost the brash style that won him early successes and united the nation after the worst terrorist attacks in U.S. history.
He would fall back on his resolve in his administration's final days, as he turned his attention to his legacy.
But President Bush leaves office a diminished figure, shunned by his own weakened party while the nation faces unprecedented challenges at home and abroad.
In an ironic twist, the partisan vitriol he endeavored to end finally shows signs of abating -- under the leadership of a successor who ran as an antidote to the Bush years.
Bush forged ahead with an ambitious agenda in Washington -- deep tax cuts, vast changes in federal social programs, expansions of executive power and a broad remaking of energy and education policies.
Claiming a mandate by simply declaring its existence, his early successes mystified his critics. With guru Karl Rove directing the action, Bush won a stunning series of political victories.
He muscled a sometimes contradictory agenda -- big tax cuts, as well as the largest Medicare expansion since the program's inception -- through a Congress that was more than willing to follow his lead.
Sept. 11, 2001, reordered the nation's priorities, and President Bush was there to reap the political bounty: He gained seats for his party in the 2002 midterm elections, with national security issues prominent in the run-up to the Iraq war.
Even when that war proved unpopular and costly, he achieved his biggest political triumph -- a convincing reelection win, and more seats in Congress for his party, in 2004.
The "permanent" Republican majority he and Rove envisioned seemed attainable as Bush plunged himself into his most ambitious legislative effort yet: a partial privatization of Social Security.
But the president who boasted about "political capital" in the heady days after his reelection saw it spent within a matter of months, sapped by a lingering war in Iraq and Democrats who found an effective voice in united opposition.
Hurricane Katrina, with its image of utter incompetence, washed away what was left of the president's political standing.
The president's second term was defined by legislative paralysis, marked by record-low approval ratings, presidential candidates who ran from his shadow, anger and anxiousness abroad and, finally, the worst domestic financial crisis in generations.
In one piece of his legacy that the president himself has said he regrets, he never made Washington a less-hostile place.
"He's left our political institutions much more troubled than they were before," said Thomas E. Mann, a senior fellow at the Brookings Institution, a Washington-based think tank. "He didn't create the ideological polarization, but he magnified it."
In his final days in office, the president would fall back on post-9/11 security and his well-known resolve in making the case that his was a successful presidency.
"I hope [Americans] feel that this is a guy that came, didn't sell his soul for politics, had to make some tough decisions, and did so in a principled way," Bush told ABC's Charles Gibson in an interview in December.