Re: Star Trek: Starships Model/Magazine Subscription
This was an original design idea, also included in the DS9 tech manual. The warhead wasn't meant to be a defensive weapon, rather a last resort weapon. Surely included when battling the Borg. I suspect that the warhead was dropped by the time the Defiant was stationed at DS9. You wouldn't wanna have something go wrong with it while docked at a station holding 7000 innocents.
"Be a pawn. Be a toy. Be a good soldier who never questions orders." Kirk to Kang - "Day of the Dove"