DARWIN, AUSTRALIA – NOVEMBER 17: U.S. President Barack Obama smiles before addressing troops at RAAF Darwin on the second day of his 2-day visit to Australia, on November 17, 2011 in Darwin, Australia. The President today laid a wreath at the USS Peary Memorial, before visiting the RAAF base, where US Army Air Force units were established during World War II. (Photo by Scott Barbour – Pool/Getty Images)