The test, in which an Aegis ballistic missile cruiser shot down a target fired from Hawaii, was the first exo-atmospheric kinetic intercept of a ballistic missile in the ascent phase of flight, and the third intercept from an Aegis warship.
Deploying a missile defense architecture that can intercept a missile early in flight (during the ascent phase) would render rogue missiles ineffective, thereby undermining the rationale to use them.