The plan for a technologically ambitious Next Generation Interceptor -- a potential decade-long project to develop a new long-range, guided missile to protect the nation against anticipated North Korean and Iranian ballistic missile threats beginning in 2030 -- is fueling a debate about the shape of the program late in the fiscal year 2021 budget endgame. That plan -- advanced by Mike Griffin, under secretary of defense for research and engineering, who in September secured support from a key Senate...