President George W. Bush has been sworn in to a second four-year term as president of the United States in a ceremony on the steps of the Capitol.
President Bush appears onstage as a curtain painted with the outline of the State of Texas parts in front of him at the Inaugural Ball in Washington
Mr Bush, who begins his second term with the lowest approval rating of any returning president except Richard Nixon, said in his inaugural address: "We have known divisions, which must be healed to move forward in great purposes, and I will strive in good faith to heal them."
He also vowed to advance democracy abroad to "break the reign of hatred and resentment" in his address, delivered on a snowy, wintry day before thousands gathered at the US Capitol and millions watching on television.
He underscored the importance of US allies at a time when many world leaders are concerned about a second Mr Bush presidency and want him to consult more.
"All the allies of the United States can know: We honor your friendship, we rely on your counsel, and we depend on your help," he said.
Shortly before he gave his address, Mr Bush put his hand on a Bible and repeated the brief oath of office given him by Mr William Rehnquist, the ailing chief justice.
A 21-gun salute rolled over the crowd after the swearing-in, punctuating a quadrennial rite attended by Washington's elite.
In his address, Mr Bush reached out to Democrats who are suspicious that he will repeat his first-term agenda of pushing conservative policies they cannot abide. He said the cause of freedom unites the country as exemplified by the united response to the September 11th, 2001, attacks that defined his first term.
"We felt the unity and fellowship of our nation when freedom came under attack, and our response came like a single hand over a single heart," he said.
Mr Bush never specifically mentioned Iraq by name in the speech, only alluding to it in saying that "for as long as whole regions of the world simmer in resentment and tyranny ... violence will gather, and multiply in destructive power, and cross the most defended borders."
"There is only one force of history that can break the reign of hatred and resentment and expose the pretensions of tyrants, and reward the hopes of the decent and tolerant, and that is the force of human freedom," he said.
"All who live in tyranny and hopelessness can know: The United States will not ignore your oppression, or excuse your oppressors. When you stand for your liberty, we will stand with you."
A number of "counter-inaugural" protests were staged, including an anti-war march. Along the route of the inaugural parade, there were plans by protesters to turn their backs on Mr Bush. Security was extremely tight for the festivities, with police erecting steel barricades and shutting down about 100 blocks of the city.
Police stood side by side along the motorcade route. Several hundred protesters chanted and waved signs that read, "Draft beer, not men," "I want to make love not war," "Four more wars," and "War begins with W."
Mr Bush, the 43rd US president, starts his second term with considerably less popular support than other recent incumbents after their re-election - an approval rating in the 50 per cent range. That is well below the support enjoyed by Presidents Dwight Eisenhower, Richard Nixon, Ronald Reagan and Bill Clinton.
Presidents traditionally get a post-inauguration honeymoon, but that may not hold true in Mr Bush's case, given the partisan divide that experts say has polarised many Americans. Democrats are already hoping to stymie his plans for revamping the Social Security retirement system and other domestic goals.
If their sharp questioning of Ms Condoleezza Rice during her Senate confirmation hearing to become secretary of state this week was any guide, Democrats plan to keep up the pressure on Mr Bush over his Iraq policy.