Turkey US Carter

A Turkish Air Force F16 fighter jet prepares to take off after Defense Secretary Ash Carter visited the Incirlik Air Base near Adana, Turkey, Tuesday, Dec. 15, 2015. Carter said the U.S. wants Turkey to better control its border with Syria, which could help block the flow of foreign fighters to the Islamic State, and to more forcefully join the U.S.-led coalition “in the air and on the ground.” Carter was in Turkey Tuesday, saying he is looking for new ways the U.S.-led coalition can strengthen its fight against Islamic State militants in Iraq and Syria.(AP Photo)

Turkish, right, and German, left, airmen stand in front of fighter jets after the U. S. Defense Secretary Ash Carter visited the Incirlik Air Base near Adana, Turkey, Tuesday, Dec. 15, 2015. Carter said the U.S. wants Turkey to better control its border with Syria, which could help block the flow of foreign fighters to the Islamic State, and to more forcefully join the U.S.-led coalition “in the air and on the ground.” Carter was in Turkey Tuesday, saying he is looking for new ways the U.S.-led coalition can strengthen its fight against Islamic State militants in Iraq and Syria.(AP Photo)

Turkey US Carter