The Obama administration's 2013 directive to bolster defense of the United States by 2017 against the North Korean ballistic missile threat could be tripped up by reliability issues stemming from the Missile Defense Agency's "optimistic and aggressive" schedule for fielding a new variant of the Ground-based Midcourse Defense interceptor, according to a congressional audit. The Government Accountability Office's 2016 statutory review of the Ballistic Missile Defense System, published April 28 , flags the potential downside associated with MDA's plan to...