Star Trek: Enterprise showed the rising Terran Empire of the 22nd century but Star Trek: Discovery truly delved into the culture and fascism of the Terran Empire, thanks to its focus on Emperor Philippa Georgiou (Michelle Yeoh) and her struggles with her adopted daughter, Michael Burnham (Sonequa Martin-Green). Star Trek: Deep Space Nine's Mirror Universe episodes revealed that the Terran Empire collapsed and was conquered by a Klingon/Cardassian alliance in the 24th century.
Introduced in the Star Trek: The Original Series episode 'Mirror Mirror,' the Mirror Universe is a parallel timeline where an Earth populated by cruel humans formed a powerful interstellar empire that conquered the Vulcans and the Klingons, among numerous races. The similarities between Star Trek: Picard season 2's fascist Federation and the Mirror Universe's Terran Empire are likely no accident.
Ironically, the Federation lacking its lofty ideals could have been the key to conquering the Borg and its Queen. In Star Trek: Picard season 2, Q (John de Lancie) changes the timeline so that the Federation is now a totalitarian regime, similar to the Terran Empire in the Mirror Universe. Star Trek: Picardseason 2's new trailer shockingly revealed that the United Federation of Planets is holding the Borg Queen (Annie Wersching) prisoner, and that implies the Mirror Universe's Terran Empire could have beaten the Borg.