Hot off his historic inauguration, President Barack Obama quickly turned his focus to drawing down troops in Iraq.
The president met with Wednesday afternoon with close advisers on his first day in office to consider complex questions surrounding the practical implications and accompanying challenges of withdrawing from Iraq. Obama aims for a phased withdrawal of U.S. troops in Iraq by the summer of 2010.
Commander of Forces Gen. Ray Odierno joined the meeting via video conference. He talked about the situation in Iraq and said he will be presenting a plan. The military has been working for months to come up with withdrawal plans that would meet Obama's 16-month goal.
Others who joined the discussion with Obama included Vice President Joe Biden, Defense Secretary Robert Gates, Chairman of the Joint Chiefs of Staff Adm. Mike Mullen, U.S. Ambassador to Iraq Ryan Crocker and Gen. David Petraeus, who flew into D.C. especially for the meeting.
"The meeting was productive and I very much appreciated receiving assessments from these experienced and dedicated individuals," Obama said in a statement after the meeting. "During the discussion, I asked the military leadership to engage in additional planning necessary to execute a responsible military drawdown from Iraq."
There are a range of options for withdrawal -- all with risks.
The most conservative of those options would be a withdrawal of forces by December 2011, which is what the U.S. agreement with the Iraqis calls for. But the risk there would be that the slower the drawdown, the slower the buildup of badly needed forces in Afghanistan.
On the other end of the spectrum, Obama's goal of withdrawing combat troops by June 2010 has some commanders fearing the move could mean an increase in violence.
Some U.S. troops have echoed those concerns.
"My only concerns would be that the lower number of troops in the country would probably lead to less security and more attacks on troops that are still left in the country," said one U.S. soldier who listened to Obama's speech Tuesday from Baghdad. "But I think it can be done."
Iraqi government spokesman Ali al-Dabbagh said Wednesday said Iraq would be open to a withdrawal of troops before December 2011, despite some concerns.
"Iraqis were worried from the premature withdrawal of the troops, but with the vision which has been clarified from the new administration, as well as the improvement in the security situation in Iraq, the Iraqi government is willing as well to have the withdrawal even before the end of 2011, taking into consideration that Iraq is working to have its security forces be ready to take the full responsibility to take full control," al-Dabbagh said.
Security is not the only challenge. Drawing down troops would also be a huge logistics challenge. In addition to returning more than tens of thousands of soldiers, massive amounts of equipment would need to be moved.
Only about 10 percent of the equipment from Iraq goes back to the U.S. via air, while the other 90 percent returns by sea on huge cargo ships. That equipment would need to move through a region that is still an active war zone, with frequent sandstorms to reach port. That could be a potential choke point that could cause massive delays.
Obama reiterated his overseas goals in Tuesday's inaugural address, after saying previous generations have faced challenges abroad "not just with missiles and tanks, but with sturdy alliances and enduring convictions."
"We will begin to responsibly leave Iraq to its people and forge a hard-earned peace in Afghanistan," the president said in his speech.
"U.S. President Barack Obama has pledged in his address to pull the American troops out of Iraq responsibly, that is to say a gradual withdrawal," said Baghdad resident Ali Abu Mustafa. "We hope he will be sincere."
Obama has also said he will leave a residual force in the region to conduct targeted counter-terrorism missions. It's not yet clear how large that force would be.
"We will not apologize for our way of life, nor will we waver in its defense, and for those who seek to advance their aims by inducing terror and slaughtering innocents, we say to you now that our spirit is stronger and cannot be broken; you cannot outlast us, and we will defeat you," Obama said at Tuesday's inaugural.
ABC News' Richard Coolidge and Kate Barrett contributed to this report.