Iran, the Korean Peninsula and the Middle Eastern peace process will also be high on his agenda, though none of them are easy tasks.

Moreover, as history shows, every new president will probably face an unexpected security issue soon after taking office.

In their first year of presidency, Clinton got Somalia and Bush was ambushed by the 9/11 terror attacks.

Time after time, an unexpected turn in world events rewrote a president's agenda and tested his ability in crisis management. Will Obama be an exception?

Finally, the greatest of all challenges may be how America deals with a fast changing geopolitical map.

A new US intelligence report says the decline of US power and the emergence of a multipolar world will be a certain trend in the next two decades.

Under such a scenario, it would certainly be much harder to "enhance the US leadership and change the world."

A team of centrists to tackle problems  

Obama will come to power with high expectations, but his presidency will be defined by not only the challenges the US is facing, but also the way he deals with them.

The Obama's cabinet is seen as a "team of rivals", because many key members are not his long-time allies. However, some scholars, including professor of Princeton university Julian Zelizer, said they would rather use the term of a "team of centrists".

Robert Gates, James Jones and Hillary Clinton are widely seen as more hawkish and conservative than the president-elect himself. However, on key policy issues, the trio isn't significantly more hawkish than Obama, analysts said, pointing to the fact all of them do not actually disagree very much with him on national security policy.

Jones has called the Iraq war a "debacle" and advocated closing the notorious detention facility at the US naval base at Guantanamo Bay, Cuba.

Gates favors a quick withdrawal from Iraq and opposes the idea of bombing Iran, while Hillary Clinton embraces a similar national security platform with Obama's.

Zelizer said the positions of Obama's key appointees and nominees are close to the centrist version.

Moreover, while Obama has built his political base among left-wing Democrats and recruited a lot of advisors who aggressively pursue a liberal agenda, when it comes to governing, the president-elect is quickly moving to the center.

On foreign policy issues, even though he took a strong stand against the Iraq war, he is no dove and he has called for the aggressive use of military force to deal with terrorists in places like Afghanistan.

"To ensure prosperity here at home and peace abroad, we all share the belief we have to maintain the strongest military on the planet," Obama has said.

A closer look into Obama's policy positions shows that he is charting a mainstream policy agenda agreed by leading figures from both parties.

(Xinhua News Agency December 9, 2008)