transition sources tell cnn mitt romney is a leading contender for secretary of state. we had a far-reaching conversation with regards to the various theaters in the world where there are interests of the united states of real significance. reporter: the 2012 republican nominee was one of trump s fiercest critics during the primaries. blasting trump s foreign policy credentials. his bombast is fueling the enmity of our enemies. political infighting is part of the game. when you go after a person who was the nominee of your party, who has been dually nominated by the voters and then you are savaging the voters, you re not just savaging donald trump. i can think of 20 other people who would be more naturally compatible with the trump vision of foreign policy. reporter: trump taking to