The suborbital one? At least this one sort of goes to orbit.
It might have been hit by something. Or it could have had a failure and blown itself up. The history of these buses and some previous observations on this satellite, plus Boeing being involved, makes me inclined to think it blew itself up.
Idk, Millennium, a Boeing subsidiary that makes satellites, just got a pretty good contract.
https://spacenews.com/millennium-space-secures-386-million-contract-for-missile-defense-satellites/