The shot was designed to improve confidence in the US missile systems , though even after the test there was considerable controversy , in part because it turned out that the warhead selected for the test had undergone modifications before testing and was not necessarily representative of the stockpile .
The shot was designed to improve confidence in the US ballistic missile systems , though even after the test there was considerable controversy . 
 This was partly because it was revealed that the warhead selected for the test had undergone modifications before testing and was not necessarily representative of the stockpile .