WASHINGTON - ? Before millions of enthusiastic onlookers, Barack Obama took the oath of office in Washington and called upon Americans to ?begin again the work of remaking America? as it faces a severe economic decline, two wars overseas and diminished international standing.

Obama, now the 44th president of the United States and the first black man to take the nation?s helm, said, ?The challenges we face are real, they are serious and they are many, they will not be met easily or in a short span of time, but know this America, they will be met.?

He said his administration would push for a ?new era of responsibility? following what he called the ?greed of a few? that has led to the nation?s worst economic climate since the Great Depression.

?Our time of standing pat, of protecting narrow interests and putting off unpleasant decisions -- that time has surely passed. Starting today, we must pick ourselves up, dust ourselves off, and begin again the work of remaking America.?

Obama, who has proposed a massive $800 billion-plus stimulus plan that would invest in the nation?s infrastructure, schools, health-care system and renewable-energy projects, cast aside ?doubters? who have raised concerns about government largesse.

He said the government isn?t too big ?if it works.?

On the international front, Obama said his administration would put greater emphasis on diplomacy and would seek to rebuild strained relationships. ?America is a friend of each nation ? we are ready to lead once more,? he said.

Obama also repeated a campaign promise to quickly pull out American troops from Iraq and put greater emphasis on the war in Afghanistan.

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Video of President Obama taking the oath of office and of his inauguration speech can also be seen on News 12 Interactive, channel 612 on your iO digital cable box.