Taking the helm of a nation beset by economic troubles and two wars, Obama told Americans on Tuesday that "starting today, we must pick ourselves up, dust ourselves off and begin the work of remaking America."
Before a crowd that swelled to more than 1 million on the National Mall, Obama assumed power over a nation longing for change after an era that that witnessed the Sept. 11, 2001 terror attacks, the beginning of wars in Afghanistan and Iraq and an economic collapse not seen since the 1930s Great Depression.
From Kenya and Indonesia, where Obama has family ties, to Asia, Europe, Africa and Latin America, his inauguration sparked a volcanic explosion of hope for better days ahead. People around the world gathered in front of their television sets to witness the moment in history, and Obama addressed them directly.
"To all the other peoples and governments who are watching today, from the grandest capitals to the small village where my father was born: 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," Obama said.
His words marked a call for personal accountability and a repudiation of the Bush years.
"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 again the work of remaking America."
Obama's 10-year-old daughter, Malia, aimed a camera at her father as he spoke. His wife, Michelle, leaned onto the edge of her seat, body tensed and brow knitted.
His speech took note of his historic place as the first black president in understated but deliberate language, and he spoke of himself as "a man whose father less than 60 years ago might not have been served at a local restaurant" yet one who now could take its most sacred oath.
Tuesday's ceremony was the culmination of a remarkable ascent for the 47-year-old Democrat, who moves into the Oval Office as the nation's fourth youngest president. In less than five years, he rose from a little-known Illinois state lawmaker to the country's highest office, persuading Americans that despite his relative inexperience, he could turn around the economy, end the Iraq war and restore U.S. standing in the world.
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."
"Every new administration talks about the challenges it faces, and they're always there," said CBS News senior political correspondent Jeff Greenfield "(But this administration) is facing challenges the likes of which have not been seen in decades. "
"And the need for celebration that the Democrats are bringing to this (is rooted in) the realization that not only are the challenges immense, but no one is entirely sure that they know what to do about them, Greenfield continued.
"I heard a very unsettling story from a prominent senator who said that in the wake of the financial crisis some months ago he called some of the most significant names in American finance and said 'Okay, if you were me what could you would you do?' and they all had the same answer, 'We don't know.'"
CBS News Chief White House correspondent Chip Reid provided some more grim analysis.
The campaign, transition and inauguration were the easy parts, Reid said. With problems such as the economy, President Obama is "jumping off a precipice and hoping for the best that he can deliver."
"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 CBS Evening News anchor Katie 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.
Immediately after the inauguration ceremony, Bush and his wife, Laura, boarded a helicopter alongside the U.S. Capitol, as they began their journey home to Texas. The new president and his wife walked them to the chopper - keeping with tradition - to see them off.
Bush flew first to Andrews Air Force Base for a private departure ceremony, then on to a welcome rally in Midland, Texas and finally, by nightfall, his ranch near Crawford, Texas.
As the architect of two unfinished wars and the man in charge at a time of economic calamity, the ex-president left Washington under the cloud of approval ratings hovering at historic lows. People in the crowd booed when Bush's image was flashed on giant screens.
Across the country on Inauguration Day Americans blew their horns, waved their flags, and cheered themselves hoarse, CBS News correspondent Dean Reynolds reports.
In Memphis, a crowd cheered, "Yes we can!"
In Miami, a supporter of President Obama said: "Oh, this is such a wonderful day. God is good."
People marched over the Edmund Pettus Bridge in Selma, Ala., where the civil rights struggle came of age.
And in Miami they marveled over the progress since those days. One resident said: "I was thinking in this same town I couldn't get a drink of water out of a fountain - and that black man is president now."
Some people had goosebumps. "You could feel everyone's excitement and everyone just standing up a little taller and really being proud to be American," said Alison Klare.
Perhaps 202 million Americans watched it all on TV, everybody awaiting the salutation history has reserved for so few: "Congratulations, Mr. President."
To rousing cheers, the new president and his wife stepped out of their limousine to greet part of the enthusiastic crowd that lined the parade route.
Among those following Obama's limousine down Pennsylvania Avenue were re-enactors from a black Civil War regiment, World War II's surviving Tuskegee Airmen - the country's first group of black military pilots and crew - and Freedom Riders who battled for civil rights.
More than 13,000 people from all 50 U.S. states traveled the 1.5-mile parade route jammed with joyous onlookers since dawn. Among the marching bands and military units are acrobats and even a drill team pushing whimsically decorated lawn mowers.
"Everybody is behind him," said Mikki Hill, 26, who traveled from Winston-Salem, N.C., and marveled at the multiracial multitudes. "Everybody's come from as far as the Earth is wide."
So it seemed on a day when change and continuity marched together in a spectacle of pageantry and raw emotion.
A couple of hours after being sworn in, Obama and his wife, Michelle, got out of their armored limousine bearing the license plate USA 1 and strolled together down the middle of Pennsylvania Avenue, holding hands and waving during the spirited inaugural parade. People along the packed parade route screeched in greeting.
The racial milestone lent a deeply personal dimension for many in the crowds as well as a historical landmark for all.
"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, after more than 20 hours of travel. Houston, who is black, said: "They'd be so proud."
At one banquet, the wealthy and powerful mingled with the powerless and poor in one thanks to the largesse of a Virginia businessman,
Energized by the moment, hordes clogged the scene, enduring below-freezing temperatures. Starting before dawn, with the Capitol bathed in lights, they streamed from jammed subway stations and thronged past parked buses, emergency vehicles and street vendors to Pennsylvania Avenue and the National Mall.
Ticket holders approaching the inaugural site filed through security sweeps in lines coiled like cinnamon rolls.
They cheered dignitaries as they came on to the inaugural stand at the Capitol. Obama walked quietly and with the merest stirring of a smile through the halls to his position on the stand and his place in history.
The crowd erupted in jubilation as he strode out.
Former Presidents Bill Clinton and George H.W. Bush, the latter walking haltingly with a cane, embraced.
Roland Pool, 47, a white social worker from Santa Fe., N.M., sized up the new president as "solid and upfront. He deals with a million people with a smile - and stoicism, too."
Elizabeth Courtman, 24, who recently moved to Washington from southern Alabama and supported Republican John McCain for president, said she came away with something to tell her children and grandchildren some day. "There's no denying the spectacle," said Courtman, who is white. "Our generation has never seen anything like this."
The grace notes of the day were not shared by all. A wave of boos greeted the introduction of Bush and his outgoing vice president, Dick Cheney, who was in a wheelchair. "Na na na na, hey hey, goodbye," some people chanted.
The World Reacts
Around the world - in countries both friendly and hostile - people people gathered around televisions to watch Obama's inauguration
In Kenya, the land of his father, they sang Barack Obama's name.
In Donegal, Ireland, they cheered in what claims to be the land of his distant cousin, and wrote new lyrics. "There's no one as Irish as Barack O'Bama!"
They rang the ceremonial bell in the town in Japan that bears his name. Yes, it's called Obama, Japan.
Never have so many felt so close, from so far away, CBS News correspondent Mark Phillips reports.
In Russia, one man said, "all of a sudden we have this smart guy running the United States
"Barack Obama really does seem to be the first American president who is also in many ways quite genuinely the world's president," said Constanze Stelzenmuller of the German Marshall Fund.
Not everyone cheered. In Gaza and the West Bank they've seen American presidents come and go - and nothing change.
One resident of Ramallah said: "Writing a speech - it's so easy to write a speech. But it doesn't mean that what he is saying, and he's just a president and he's not going to do anything new in Palestine."
But elsewhere, he's already done something new.
In Paris, Maria Laloux said: "For me it's a miracle. Martin Luther Kind said, 'We hall overcome.' We did today."
A Few Sour Notes
In spite of the massive crowds attending the inauguration, sources at the Washington, D.C. police department and the U.S. Park Police - which has jurisdiction over the national mall - told CBS News that they made no arrests today.
It was a day of high spirits - jarred by sudden concern about the health of Sen. Edward M. Kennedy, a legendary Democrat who is suffering from brain cancer.
He was rushed, convulsing, from a post-inauguration 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 said later that Kennedy was awake and conversing with family at the hospital, and that the seizure had been prompted by fatigue. They said Kennedy would remain at Washington Hospital Center overnight for evaluation.
Earlier Tuesday, a 68-year-old woman was injured when she fell on the Metro tracks and was hit by a train.
The district fire department responded to dozens of calls from people falling down or complaining of the being cold, D.C. fire and EMS department spokesman Alan Etter said. About two dozen were hospitalized.
Etter said medical personnel were having trouble getting to people quickly around the mall because of the throngs of people, but he added that everyone who needed help has eventually received treatment.
On To The Balls
Washington spent the afternoon celebrating with a parade, and the festivities won't end until well after midnight, with Washingtonians dancing and partying at dozens of inaugural balls.
The Obamas themselves planned to attend 10.
They started the night at the Neighborhood Ball where Beyonce serenaded them with Etta James' "At Last" as they slowly danced. Across the capital, there were at least a dozen other unofficial balls where partiers were celebrating even without an appearance from the new first couple.
The president pulled his wife close and they danced a slow, dignified two-step while, offstage, Beyonce sang. The president spun first lady Michelle Obama once in a half-turn.
Obama cut loose in a faster groove a few minutes later, as Shakria, Mary J. Blige, Faith Hill and Mariah Carey sang along with Stevie Wonder to his "Sign, Sealed, Delivered." The song was played at nearly every one of Obama's rallies throughout the campaign.
The president wore white tie, while Michelle shimmered in a white, one-shouldered, floor-length gown. It was embellished from top to bottom with white floral details and made by designer Jason Wu.
Obama asked the crowd of celebrities and supporters alike, "How good looking is my wife?"
The new president said the ball, for people who live in Washington area and which was broadcast live on ABC, best captured the spirit of his campaign.
"We got the idea for the neighborhood ball because we are neighborhood people," he said. "I cut my teeth doing neighborhood work. And this campaign was organized neighborhood by neighborhood."