@npr: Over the weekend, the U.S. removed a dozen B-1 bombers from a British air base near where five men were arrested last week in a suspected terror plot. A U.S. official who is not authorized to speak publicly told NPR that the decision to abruptly send home a dozen B-1 bombers from Royal Air Force base Fairford was due to a "credible threat" from Iran, which potentially involved a drone attack. The threat comes after a number of U.S. bases in the Gulf have been attacked as part of the ongoing conflict with Iraq. Has the U.S. entered a new era when its presence poses a threat to its allies? “Sources & Methods” host Mary Louise Kelly breaks it down with NPR Pentagon Correspondent Tom Bowman. Listen to the full episode at the link in our bio. #NPR