Images of the president in his role as head of the U.S. military.
U.S. Army Gen. David Petraeus, commander of the Multi-National Force in Iraq, gives then-Sen. Barack Obama an aerial tour over Baghdad on July 21, 2008. Sen. Chuck Hagel (R-Neb.) and Sen. Jack Reed (D-R.I.) joined the presidential candidate on his tour of the Middle East and Europe.Lorie Jewell/U.S. ARMY