Democratic presidential candidate Barack Obama, left, rides inside a helicopter with David Petraeus, center, top U.S. military commander in Iraq, and Sen. Chuck Hagel, R-Neb, in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, right, is greeted by the top U.S. military commander in Iraq, David Petraeus, center, upon his arrival to Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, left, and David Petraeus, ride inside a helicopter in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, right, is greeted by the Iraqi Prime Minister Nouri al-Maliki, left, in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, left, shakes hands with the Iraqi Prime Minister Nouri al-Maliki in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, center, leaves after having talks with Iraqi Prime Minister Nouri al-Maliki, unseen, in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, third from left, Iraqi President Jalal Talabani, fourth from left, and unidentified aides walk out after their meeting in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama laughs as he talks to the Iraqi President Jalal Talabani, unseen, in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, left, talks to the Iraqi President Jalal Talabani in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, left, walks with Iraqi government spokesman Ali al-Dabagh, second from left, and Iraqi national security advisor Mowafak al-Rubaie, right, as he enters the office of the Iraqi Prime Minister Nouri al-Maliki, unseen, in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, front right, and the U.S. ambassador to Iraq, Ryan Crocker, front left, leave after having talks with Iraqi Prime Minister Nouri al-Maliki, unseen, in Baghdad, Iraq, Monday, July 21, 2008.
Sen. Barack Obama, right, speaks with Sgt. 1st Class Ishanna Fenton of Combined Security Transition Command in Afghanistan over breakfast during a visit to Camp Eggers in Kabul, Afghanistan, Sunday, July 20, 2008.
Sen. Barack Obama, third from right, is photographed Saturday July 19, 2008, at Bagram airbase in Afghanistan. Obama is posing with Sen. Chuck Hagel, R-Neb., second left, and Sen. Jack Reed, D-R.I., second right. Third from left is Maj. Gen. Jeffrey J. Schloesser and far right is Sgt. Maj. Vincent Camacho. At far left is U.S. Ambassador to Afghanistan William Braucher Wood.
Sen. Barack Obama, center, as he arrives for a meeting with Afghan President Hamid Karzai, unseen, at the Presidential Palace in Kabul, Sunday, July 20, 2008.
In this photo released Saturday, July 19, 2008, by the the U.S. Army, Sen. Barack Obama, D-Ill., waves as he leaves the gym after talking to service members at Camp Arifjan, Kuwait, Friday, July 18, 2008, during a Congressional Delegation visit.
Sen. Barack Obama shakes hands with service members at Camp Arifjan, Kuwait, Friday, July 18, 2008, during a Congressional Delegation visit.