A horror scenario eluded to in a book I read is a typical container ship off NYC that elevates a missile container and launches away. The Norks and Iranitards have the ability to do this. Nothing stops this but intelligence and inspection before such a terror ship gets within range of a major American port.
I know something about radars. I think that if a competent missile interceptor specifically designed and paired with its complement radar can track and launch, and can beam switch (e.g., AESA, ESA, etc.) track and hit the missile, then it will work. That requires a very expensive high frequency agile radar, like a THAAD variant.
The fault lays in the misconception an integrated system of L and S-band radars in the SPY-1 genre can co-register tracking positions and somehow boil all that into a target solution for an X or K-band radar/missile system is optimistic at best in my opinion.