Obama Meets US Special Forces Commandos

President Barack Obama walks down the stairs from Air Force One upon arrival at Andrews Air Force Base, Md. on Friday, May 6, 2011.(AP Photo/Jose Luis Magana)

Soldiers salute the flag during the Pledge of Allegiance before an appearance by President Barack Obama and Vice President Joe Biden at Fort Campbell, Ky., Friday, May 6, 2011. Obama and Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

A soldier photographs Vice President Joe Biden as he speaks to troops at Fort Campbell, Ky., Friday, May 6, 2011. President Barack Obama and Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

President Barack Obama speaks to troops at Fort Campbell, Ky., Friday, May 6, 2011. Obama and Vice President Joe Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

President Barack Obama speaks to troops at Fort Campbell, Ky., Friday, May 6, 2011. Obama and Vice President Joe Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

President Barack Obama greets military personnel who have recently returned from Afghanistan after speaking about the mission that resulted in the death of Osama bin Laden at Fort Campbell, Ky., Friday, May 6, 2011. (AP Photo/Charles Dharapak)

President Barack Obama, left, displays a shirt given to him by troops as Vice President Joe Biden is seen at right after they spoke to military personnel who have recently returned from Afghanistan at Fort Campbell, Ky., Friday, May 6, 2011. (AP Photo/Charles Dharapak)

President Barack Obama, accompanied by Vice President Joe Biden, holds up a shirt given to him as he greeted military personnel who have recently returned from Afghanistan, Friday, May 6, 2011, at Fort Campbell, Ky. (AP Photo/Charles Dharapak)

President Barack Obama, right, and Vice President Joe Biden rally military personnel at Fort Campbell, Ky., who have recently returned from Afghanistan after speaking about the mission that resulted in the death of Osama bin Laden, Friday, May 6, 2011. (AP Photo/Charles Dharapak)

President Barack Obama pauses as he speaks to troops at Fort Campbell, Ky., Friday, May 6, 2011. Vice President Joe Biden applauds at left. Obama and Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

President Barack Obama speaks to troops as Vice President Joe Biden, left, listens at Fort Campbell, Ky., Friday, May 6, 2011. Obama and Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

President Barack Obama, accompanied by Vice President Joe Biden, gestures as he speaks to troops at Fort Campbell, Ky., Friday, May 6, 2011. Obama and Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

President Barack Obama greets troops after speaking at Fort Campbell, Ky., Friday, May 6, 2011. Obama and Vice President Joe Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

President Barack Obama greets military personnel who have recently returned from Afghanistan after speaking about the mission that resulted in the death of Osama bin Laden at Fort Campbell, Ky., Friday, May 6, 2011. (AP Photo/Charles Dharapak)

President Barack Obama greets troops after speaking at Fort Campbell, Ky., Friday, May 6, 2011. Obama and Vice President Joe Biden came to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)

President Barack Obama addresses military personnel who have recently returned from Afghanistan, Friday, May 6, 2011, at Fort Campbell, Ky. (AP Photo/Charles Dharapak)

President Barack Obama addresses military personnel who have recently returned from Afghanistan, Friday, May 6, 2011, at Fort Campbell, Ky. (AP Photo/Charles Dharapak)

President Barack Obama addresses military personnel who have recently returned from Afghanistan, Friday, May 6, 2011, at Fort Campbell, Ky. (AP Photo/Charles Dharapak)

President Barack Obama greets military personnel prior to addressing troops, Friday, May 6, 2011, at Fort Campbell, Ky. (AP Photo/Charles Dharapak)

Soldiers arrive in a hangar to hear an address by President Barack Obama at Fort Campbell, Ky., Friday, May 6, 2011. Obama is coming to Fort Campbell to address soldiers who have recently returned from Afghanistan. (AP Photo/Mark Humphrey)