Stepping into history, Barack Obama grasped the reins of power as America's first black president Tuesday, declaring the nation must choose "hope over fear, unity of purpose over conflict and discord" to overcome the worst economic crisis since the Great Depression.
After the swearing-in ceremony and inaugural address, President Obama stepped out of his limousine to greet part of the enthusiastic crowd that lined the route of his inaugural parade.
Obama and his wife, Michelle, got out of their car on Pennsylvania Ave., waved to the cheering spectators on both sides of the street, and then walked part of the way, smiling and waving.
A couple of moments later, Vice President Joe Biden and his wife, Jill, joined them on the walk.
President Jimmy Carter was the only president to march all the way along his inaugural parade route, reports CBS Evening News anchor Katie Couric, though Bill Clinton and George H.W. Bush did walk part of the way.
Along the way, hundreds of people who had been packed on rooftops and balconies broke into loud cheers. They got an unobstructed view of the parade from above the large crowd.
The four walked for about seven minutes before getting back into their limousines.
The parade route has also been lined with police and military personnel, who have saluted as the new president's limousine slowly moved past them.
At first light hundreds of thousands of people were already streaming onto the National Mall, reports CBS News Capitol Hill correspondent Chip Reid.
While the President-elect and First Lady-to-be had coffee with the outgoing President and his wife, the flood of humanity continued, despite weather so cold the Reflecting Pool at the Washington Monument was frozen solid. The crowd eventually reached about 2 million, five times the number that turned out four years ago for the second inauguration of George W. Bush.
By comparison, in 1981, President Ronald Reagan's inauguration drew about 500,000 people, and President Bill Clinton's 1993 inauguration drew about 800,000 people, according to National Park Service estimates.
On the National Mall, the crowd stretched nearly two miles - from the Capitol building to the steps of the Lincoln Memorial, where civil rights leader Martin Luther King Jr. delivered his "I Have a Dream" speech.
The bulk of the crowd was jammed into the area between the west front of the Capitol and the Washington Monument, where people stood shoulder-to-shoulder as Barack Obama was sworn in as the 44th president. The crowd was so tightly packed that some people complained they felt claustrophobic.
The vast, excited crowd bore witness to a transfer of American power like none before it. The blare of regal trumpets and thunder of cannon were familiar. The transition from Republican to Democrat, and gray hair to dark, had happened before.
But this was white to black, a shattering of racial barriers finally made complete when Barack Obama made it through a bumbled oath-taking, delivered a momentous-by-definition speech and got back to being his unflappable self.
The Democrat who charged onto the national scene saying this was not a nation of red states and blue states, but the United States, became president while wearing a red tie, the Republican color.
Republican George W. Bush, president no more, wore a blue tie, the Democratic color. They embraced at the Capitol and walked out together.
The racial milestone lent a deeply personal dimension for many in the crowd as well as a historical landmark for all.
New York Governor David Patterson told Couric that Obama's inauguration was "a fulfillment of a dream that African-Americans, both the living and the dead, have struggled for, for a couple of centuries to build a movement that would bring economic, political and social justice to African-Americans.
"But really what touched me was the effect that this inauguration has had on white Americans. People who didn't vote for President Obama, presumably might not vote for him for re-election and wouldn't agree with his policies still see the historical significance."
"I've been real emotional all morning thinking about my grandmother and the heroes whose shoulders we stand on," said Lyshundria Houston, 34, here from Memphis, Tenn., after more than 20 hours of travel. Houston, who is black, said: "They'd be so proud."
Coming from the city where Martin Luther King Jr. was assassinated, she reflected on the civil rights movement on her way to the parade, and said: "Sometimes that makes the cold go away."
Garth Baylor, 54, a carpenter, said no inaugural celebration could compare to this one.
"I went to Clinton's inauguration. It was nothing like this," Baylor said. "I don't think Washington has ever had this many visitors all at once."
Crowds were so thick that medical personnel were having trouble getting to people quickly around the Mall, fire department spokesman Alan Etter said. Still, he said everyone who has needed help eventually received treatment.
With 11 million Americans out of work and trillions of dollars lost in the stock market's tumble,left behind by outgoing President Bush.
"Our time of standing pat, of protecting narrow interests and putting off unpleasant decisions - that time has surely passed," Obama said. "Starting today, we must pick ourselves up, dust ourselves off and begin the work of remaking America."
"There was no crescendo moment and I think it was intended that way," Vernon Jordan, a close adviser to former President Bill Clinton, said of Mr. Obama's speech during a conversation with Couric. Instead, Jordan described the speech as one about governing, one that fostered a "let's do it together" attitude toward the challenges facing the nation.
One somber note hung over the celebrations, however, as reports circulated that Sen. Ted Kennedy, D-Mass., suffered a seizure at the Inaugural lunch. "I would be lying to you if I did not say that right now a part of me is with him," President Obama said of Kennedy.
Kennedy, a legendary Democrat who is suffering from brain cancer, was rushed from a Senate luncheon in honor of Obama. "This is a joyous time but it's also a sobering time," Obama said. "And my prayers are with him and his family and (Kennedy's wife) Vicki."
Doctors later reported that Kennedy's seizure was caused by fatigue. Dr. Edward Aulisi, Washington Hospital Center's neurosurgery chairman, says Kennedy is awake, talking with family and friends and feeling well.
In a statement released by Kennedy's office, Aulisi said: "After testing, we believe the incident was brought on by simple fatigue."
There was a touch of FDR's famous inaugural in Obama's blunt recitation of our woes, reports CBS News senior political correspondent Jeff Greenfield.
"Our economy is badly weakened a consequence of greed and irresponsibility on the part of some, but also our collective failure to make hard choices. Homes have been lost, jobs shed, businesses shuttered."
And, as with Roosevelt, there was an optimistic promise, Greenfield reports.
"Today I say to you that the challenges we face are real. They are serious and they are many. They will not be met easily or in a short time. But know this, America - they will be met."
There was an echo of John Kennedy, speaking to the world beyond our borders, Greenfield reports.
"To all other people's and governments who are watching today, know that America is a friend of each nation, and every man, woman and child who seeks a future of peace and dignity, and that we are ready to lead once more."
"It is a brave, new, refreshing message in the world of politics; a message that our new leaders recognize their limitations, understand that they will make mistakes, and believe that they can succeed better and more quickly in their plans and goals only with help from those of the rest of us who are willing to come to them with good deeds and constructive ideas," writes CBS News legal analyst Andrew Cohen.
Two years after beginning his improbable quest as a little-known, first-term Illinois senator with a foreign-sounding name, Obama moved into the Oval Office as the nation's fourth-youngest president, at 47, and the first African-American, a barrier-breaking achievement believed impossible by generations of minorities.
He said it was a moment to recall "that all are equal, all are free and all deserve a chance to pursue their full measure of happiness." In another racial reference, he paid tribute to workers in the past who "endured the lash of the whip and plowed the hard earth."
A mighty chorus of cheers erupted as he stepped to the inaugural platform, a midday sun warming the crowd that had waited for hours in the cold. There were some boos when Bush and Vice President Dick Cheney came onto the platform.
The dawn of the new Democratic era - with Obama allies in charge of both houses of Congress - ends eight years of Republican control of the White House by Bush, who leaves Washington as one of the nation's most unpopular and divisive presidents, the architect of two unfinished wars and the man in charge at a time of economic calamity that swept away many Americans' jobs, savings and homes.
Obama called for a political truce in Washington to end "the petty grievances and false promises, the recriminations and worn-out dogmas, that for far too long have strangled our politics."
He said that all Americans have roles in rebuilding the nation by renewing the traditions of hard work, honesty and fair play, tolerance, loyalty and patriotism.
With the economy in a long and deepening recession, Obama said it was time for swift and bold action to create new jobs and lay a foundation for growth. Congressional Democrats have readied an $825 billion stimulus plan of tax cuts and spending for roads, bridges, schools, electric grids and other projects.
Contradicting the objections of Ronald Reagan and Bill Clinton to big government, Obama said, "The question we ask today is not whether our government is too big or too small, but whether it works."
After the ceremony, Obama and his wife escorted Bush and his wife to a helicopter on the East Front of the Capitol for the trip to nearby Andrews Air Force Base and a flight back home to Texas.
It was the first change of administrations since the terror attacks of Sept. 11, 2001.
Bush - following tradition - left a note for Obama in the top drawer of his desk in the Oval Office.
White House press secretary Dana Perino said the theme of the message - which Bush wrote on Monday - was similar to what he has said since election night: that Obama is about to begin a "fabulous new chapter" in the United States, and that he wishes him well.
The unfinished business of the Bush administration thrusts an enormous burden onto the new administration, though polls show Americans are confident Obama is on track to succeed. He has cautioned that improvements will take time and that things will get worse before they get better.
Culminating four days of celebration, the nation's 56th inauguration day began for Obama and Vice President-elect Joe Biden with a traditional morning worship service at St. John's Episcopal Church, across Lafayette Park from the White House. Bells pealed from the historic church's tower as Obama and his wife, Michelle, arrived five minutes behind schedule.
The festivities weren't ending until well after midnight, with dancing and partying at 10 inaugural balls.
By custom, Obama and his wife, and Biden and his wife, Jill, went directly from church to the White House for coffee with Bush and his wife, Laura. Michelle Obama brought a gift for the outgoing first lady in a white box decorated with a red ribbon.
Shortly before 11 a.m., Obama and Bush climbed into a heavily armored Cadillac limousine to share a ride to the Capitol for the transfer of power, an event flashed around the world in television and radio broadcasts, podcasts and Internet streaming.
Just after noon, Obama stepped forward on the West Front of the Capitol to lay his left hand on the same Bible that President Abraham Lincoln used at his first inauguration in 1861. The 35-word oath of office, administered by Chief Justice John Roberts, has been uttered by every president since George Washington. Obama was one of 22 Democratic senators to vote against Roberts' confirmation to the Supreme Court in 2005.
The son of a white, Kansas-born mother and a black, Kenya-born father, Obama decided to use his full name in the swearing-in ceremony.
To the dismay of liberals, Obama invited conservative evangelical pastor Rick Warren - an opponent of gay rights - to give the inaugural invocation.
About a dozen members of Obama's Cabinet and top appointees were ready for Senate confirmation Tuesday, provided no objections were raised. But Republican Sen. John Cornyn of Texas indicated he would block a move to immediately confirm Secretary of State-designate Hillary Rodham Clinton. Still, she is expected to be approved in a roll call vote Wednesday.
More than 10,000 people from all 50 states - including bands and military units - were assembled to follow Obama and Biden from the Capitol on the 1.5-mile inaugural parade route on Pennsylvania Avenue, concluding at a bulletproof reviewing stand in front of the White House. Security was unprecedented. Most bridges into Washington and about 3.5 square miles of downtown were closed.
Among the VIPs at the Capitol was pilot Chesley "Sully" Sullenberger, the hero of last week's US Airways crash into the Hudson River.
In an appeal for bipartisanship, Obama honored defeated Republican presidential rival John McCain at a dinner Monday night. "There are few Americans who understand this need for common purpose and common effort better than John McCain," Obama said.
Young and untested, Obama is a man of enormous confidence and electrifying oratorical skills. Hopes for Obama are extremely high, suggesting that Americans are willing to give him a long honeymoon to strengthen the economy and lift the financial gloom.
On Wednesday, his first working day in office, Obama is expected to redeem his campaign promise to begin the withdrawal of U.S. forces from Iraq under a 16-month timetable. Aides said he would summon the Joint Chiefs of Staff to the Oval Office and order that the pullout commence.