In his brief, 18-minute speech, Obama did not dwell on the most pressing challenges of the past four years. He barely mentioned the struggle to reduce the federal deficit, a fight that has occupied much of his and Congress' time and promises the same in months to come.
He spoke up for the poor -- "Our country cannot succeed when a shrinking few do very well and a growing many barely make it" -- and for those on the next-higher rung -- "We believe that America's prosperity must rest upon the broad shoulders of a rising middle class." The second reference echoed his calls from the presidential campaign that catapulted him to re-election.
"A decade of war is now ending. An economic recovery has begun," said the president who presided over the end to the U.S. combat role in Iraq, set a timetable for doing the same in Afghanistan and took office when the worst recession in decades was still deepening.
"We will support democracy from Asia to Africa, from the Americas to the Middle East, because our interests and our conscience compel us to act on behalf of those who long for freedom," he said in a relatively brief reference to foreign policy.
The former community organizer made it clear he views government as an engine of progress. While that was far from surprising for a Democrat, his emphasis on the need to combat global climate change was unexpected, as was his firm new declaration of support for full gay rights.
In a jab at climate-change doubters, he said, "Some may still deny the overwhelming judgment of science, but none can avoid the devastating impact of raging fires and crippling drought and more powerful storms." He said America must lead in the transition to sustainable energy resources.
He likened the struggle for gay rights to earlier crusades for women's suffrage and racial equality.
"Our journey is not complete until our gay brothers and sisters are treated like anyone else under the law -- for if we are truly created equal, then surely the love we commit to one another must be equal as well," said the president, who waited until his campaign for re-election last year to announce his support for gay marriage.
His speech hinted only barely at issues likely to spark opposition from Republicans who hold power in the House.
He defended Medicare, Medicaid and Social Security as programs that "do not make us a nation of takers; they free us to take the risks that made this country great."
He referred briefly to making "the hard choices to reduce the cost of health care and the size of our deficit," a rhetorical bow to a looming debate in which Republicans are seeking spending cuts in health-care programs to slow the rise in a $16.4 trillion national debt.
He also cited a need for legislation to ease access to voting, an issue of particular concern to minority groups, and to immigration reform and gun-control legislation that he is expected to go into at length in his State of the Union speech Feb. 12.
But his speech was less a list of legislative proposals than a plea for tackling challenges.
"We must act, knowing that our work will be imperfect," he said, and today's "victories will only be partial."
There was some official business conducted during the day.
Moments after being sworn in, the president signed nomination papers for four new appointees to his Cabinet, Sen. John Kerry for secretary of state, White House chief of staff Jacob Lew to be treasury secretary, former Nebraska Sen. Chuck Hagel for defense secretary and White House adviser John Brennan to head the CIA.
Associated Press writers Larry Margasak, Darlene Superville, Donna Cassata, Alan Fram, Andrew Taylor, Stephen Ohlemacher, Jim Kuhnhenn, Julie Pace, Tom Ritchie and Tracy Brown, in Washington; Adrian Santz in Memphis, Tenn., and Stephen Singer in Hartford, Conn., contributed to this story.