Star Trek: Deep Space Nine needed the USS Defiant, and the game-changing season 2 finale proved exactly why Commander Benjamin Sisko (Avery Brooks) needed his own starship. In Star Trek: DS9 season 2, episode 26, “The Jem’Hadar”, a holidaying Sisko encounters the titular villains for the first time, setting up Deep Space Nine‘s Dominion War arc. When Sisko is captured by the Jem’Hadar, Starfleet sends the Galaxy-class USS Odyssey and the DS9 crew into the Gamma Quadrant to investigate, leading to the first battle in the so-called Dominion Cold War.
The battle against the Jem’Hadar in Star Trek: Deep Space Nine‘s season 2 finale exacted a devastating toll on Starfleet and the Federation. Unprepared for the Dominion’s brutal footsoldiers, the USS Odyssey was destroyed with all hands. As the USS Odyssey was a Galaxy-class starship like Star Trek: The Next Generation‘s version of the starship Enterprise, its destruction signposted that the Jem’Hadar and the Dominion were a serious threat to the Federation. In light of this, it was decided that DS9’s stationary location just wouldn’t cut it against this existential threat to Starfleet.
Star Trek: Deep Space Nine‘s production team decided that the Jem’Hadar should destroy a Galaxy-class starship to prove the strength of the Dominion. However, this decision then gave them another problem to deal with. Remembering the making of the season 2 finale in Captains’ Logs Supplemental – The Unauthorized Guide to the New Trek Voyages by Edward Gross and Mark A. Altman, Ira Steven Behr discussed how blowing up an Enterprise starship in DS9 created a new problem.
While the runabouts were able to evade the Jem’Hadar in the Star Trek: Deep Space Nine season 2 finale, it’s only because the Dominion wanted them to return to Federation space and deliver a warning. While in pre-production on DS9 season 3, it was decided that the Danube-class runabouts simply wouldn’t be able to defend Deep Space Nine from an attack by the Dominion. What Sisko and the DS9 crew needed was a fighting starship that could be deployed to the Gamma Quadrant to learn more about the impending threat of the Dominion and the Jem’Hadar.
In-universe, Starfleet felt exactly the same as Star Trek: Deep Space Nine‘s production team, and furnished Sisko with the USS Defiant NX-74205 in the season 3 premiere, “The Search, Part I”. The NX-74205 was the second of four Star Trek ships named Defiant, and is the best-loved in the canon. Sisko’s Defiant started life in the wake of the Battle of Wolf 359, as Starfleet and the Federation authorized the development of its first warship in decades. However, development of the Defiant hit a stumbling block when the design team, which included Commander Sisko, couldn’t fix the issues arising from the ship’s powerful engines.
The Defiant project was shuttered when the threat from the Borg Collective subsided, so the prototype was placed in storage and Sisko was assigned to Deep Space Nine. Following the events of Star Trek: Deep Space Nine‘s season 2 finale, Commander Sisko requested that the USS Defiant be assigned to the station. Starfleet granted Sisko’s request, and the ship was launched in 2370 from the Antares Shipyards. In early 2371, the USS Defiant arrived at Deep Space Nine for its first mission into the Gamma Quadrant. It would be the first of many vitally important missions for Sisko’s “tough little ship“.
All episodes of Star Trek: Deep Space Nine are available to stream on Paramount+.