As Barack Obama prepares to confront Iran and other issues, Indian students donned his image to urge a curb on terrorism.

WASHINGTON , DAVID E.SANGER ESSAY

THE WORLD LOOKED very different on the frigid Saturday in February 2007 when Barack Obama stood in front of the Old State Capitol in Springfield, Illinois, and declared himself a candidate for president of the United States.


The “surge” in Iraq was in its first weeks, and it seemed hard to imagine that by the time the next president took office, in 710 days, there would be a consensus about the pace of an American withdrawal. The two Palestinian factions, Hamas and Fatah, were talking about a peaceful power-sharing agreement.


The Dow was at 12,580, on the way to 14,000 that summer. General Motors was making money selling cars even while reporting some concerns about “nonprime mortgages” held by its financing division.
And the greatest worries about China and India were that their economies were growing so fast they could overheat.


The challenges that Mr. Obama will begin to confront now, in short, bear little resemblance to those from two years ago when he conceded that “there is a certain presumptuousness in this - a certain audacity - to this announcement.”


The agenda he is setting out to enact now is significantly altered from what he had in mind then, partly by choice but mostly by circumstance. Over the past two years, and especially in the two and a half months since his election, he has spoken less and less about Iraq and more and more about stabilizing the world economy. Behind the scenes, his national staff has raced to reassess strategies for Afghanistan, Gaza, Iran and Pakistan, even before logging on to their secure computers in the West Wing.


“He’s facing the classic problem of having to handle a number of crises before he’s really got time to set out a long-term architecture,” said G. John Ikenberry, a Princeton University professor who co-wrote a detailed study of the national security agenda for whoever became the next president. Former Secretary of State Madeleine K.Albright called Mr. Obama’s task analogous to “redesigning the airplane while you’re flying it.”


But the shifting reality has done more than force a change in focus.
It also led Mr. Obama to re-examine his assumptions about a range of issues, hone his thinking and reach out to new advisers, some of them drawn from Senator Hillary Rodham Clinton’s presidential campaign .

Aides to Mr. Obama since his arrival in the Senate say his views have not changed as much as some liberal supporters and commentators contend. From the day in 2002 when he stated opposition to the Iraq war, he has said he is not against all wars. And on some issues, including that of striking at terrorism targets in Pakistan, he has sometimes been to the right of both Democratic and Republican rivals.


Two years ago, Mr. Obama’s views on Iraq dominated the headlines as he began his campaign by emphasizing his differences with Mrs.
Clinton. Then, it would have been hard to imagine that in less than two years he would ask President Bush’s defense secretary, Robert M.
Gates, to stay on, along with the White House “war czar” for Iraq and Afghanistan. In March, Mr. Obama began talking about Iran as the nation that “poses the greatest challenge to American interests in the Middle East in a generation,” and he vowed a few months later never to let the country obtain a nuclear weapon.


His openness to many viewpoints on national security has become more pronounced with each daily presidential briefing and with closer study of National Intelligence Estimates, which his staff says he reads with some skepticism. That is not only because of what the intelligence agencies got wrong in the run-up to the war in Iraq.
“He approaches the intelligence reports the same way he approaches a lot of the things he reads, whether it’s a story in The New York Times or a report from the ground,” said Denis McDonough, a longtime foreign policy aide who is often charged with finding answers to questions Mr. Obama raises. He contends that those who think Mr. Obama has drifted toward more hawkish views were not listening to what he said during the campaign about Iran or Pakistan or Hamas.


One official who is reported to be headed for a senior position in the administration and would not talk on the record until his confirmation said: “Everyone focused on his willingness to engage the Iranians in direct talks, and that was the right thing to do.
But they don’t listen to the part that says that if the Iranians don’t come to the table, he’s prepared to talk about cutting off their gasoline and squeezing them on sanctions.”


Mr. Obama has renewed his pledge to engage directly with the Iranians, something Mr. Bush permitted only recently and only at a low government level. Mrs. Clinton, who once cast Mr. Obama’s calls for high-level engagement as an example of his inexperience, will now be in charge of the effort.


But the enterprise is bound to be complicated by the fact that Mr. Bush is handing off to his successor an expanded, covert effort to undermine the Iranian nuclear program, one of many secret programs that Mr. Obama has been briefed about recently and will soon have the opportunity to reauthorize, modify or terminate.