The March flight test of the Ground-based Midcourse Defense system -- a developmental assessment that marked the first salvo launch of Ground-based Interceptors hailed as a landmark achievement by program boosters -- was 13 years behind schedule and was built on a record of GMD tests that have achieved less than 50 percent operational realism, according to congressional investigators. The Government Accountability Office notes these two key points in its annual missile defense report to lawmakers , details that neither...