Former CIA director, author of the book'Undaunted,' John Brennan provides insight on'Fox News Sunday.' The U.S. military flew a pair of B-52 bombers to the Middle East Thursday from Barksdale AFB in Louisiana the second deterrence mission against Iran in recent weeks and comes on the same day U.S. drones attacked al-Qaeda-linked'explosives experts' in Somalia. "We have seen some indications of increased attack planning by Iranian-linked forces inside Iraq" said one U.S. military official who declined to be identified to discuss the sensitive nature of the information. "Presidential transitions are normally a time when our adversaries try to test us," the official added. U.S. military forces are drawing down to 2,500 in Iraq and Afghanistan before January 20th.