U.S. President Barack Obama yawns at the beginning of the East Asian Summit Plenary Session at the Peace Palace in Phnom Penh, Cambodia, Tuesday, Nov. 20, 2012. Seated left is Japan's Prime Minister Yoshihiko Noda, and right is Chinese Premier Wen Jiabao. (AP Photo/Carolyn Kaster)

Associated Press
U.S. President Barack Obama yawns at the beginning of the East Asian Summit Plenary Session at the Peace Palace in Phnom Penh, Cambodia, Tuesday, Nov. 20, 2012. Seated left is Japan's Prime Minister Yoshihiko Noda, and right is Chinese Premier Wen Jiabao. (AP Photo/Carolyn Kaster)
U.S. President Barack Obama yawns at the beginning of the East Asian Summit Plenary Session at the Peace Palace in Phnom Penh, Cambodia, Tuesday, Nov. 20, 2012. Seated left is Japan's Prime Minister Yoshihiko Noda, and right is Chinese Premier Wen Jiabao. (AP Photo/Carolyn Kaster)