WASHINGTON - January 20, 2009 - Stepping into history, Barack Hussein Obama grasped the reins of power as America's first black president on Tuesday, saying the nation must choose "hope over fear, unity of purpose over conflict and discord" to overcome the worst economic crisis since the Great Depression.

In frigid temperatures, an exuberant crowd of more than a million packed the National Mall and parade route to celebrate Obama's inauguration in a high-noon ceremony. They filled the National Mall, stretching from the inaugural platform at the U.S. Capitol to the Lincoln Memorial in the distance.

With 11 million Americans out of work and trillions of dollars lost in the stock market's tumble, Obama emphasized that his biggest challenge is to repair the tattered economy left behind by outgoing President George W. Bush.

"Our time of standing pat, of protecting narrow interests and putting off unpleasant decisions - that time has surely passed," said Obama in an undisguised shot at Bush regime policies. "Starting today, we must pick ourselves up, dust ourselves off and begin the work of remaking America."

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's election was cheered around the world as a sign that America will be more embracing and more open to change. "To the Muslim world," Obama said, "we seek a new way forward, based on mutual interest and mutual respect."