Miles O'Brien (mirror)

In the mirror universe Miles O'Brien was a Terran slave of the Klingon-Cardassian Alliance with a theta designation until 2370. With the death of Benjamin Sisko a year later, he became leader of the Terran Rebellion.

Terran Rebellion Career
When Sisko first met O'Brien in 2369, O'Brien's serious demeanor was so noticeable that Sisko decided to designate O'Brien as "Smiley",a name that stuck thereafter.

In 2370, he was working in the ore processing facility on Terok Nor when he encountered the primary universe Julian Bashir. He and Sisko later helped Bashir and primary universe Kira Nerys escape from the station, and the clutches of Intendant Kira Nerys.

In 2371, O'Brien visited the primary universe and abducted that version of Benjamin Sisko, bringing him back to our universe. There, the two men persuaded Professor Jennifer Sisko to abandon her work on a transpectral sensor array. Jennifer did so, and even joined the Rebellion.

Creation of New Defiant
Whilst O'Brien was in the primary universe, he secretly downloaded numerous computer files from Deep Space 9's computer system, including complete plans for USS Defiant. In early 2372, O'Brien was among the rebels who commandeered Terok Nor from the Alliance and imprisoned Intendant Kira. Having by this time constructed their own Defiant. They were disappointed when they discovered it had significant technical faults that prevented it becoming operational. O'Brien once again worked with the primary-Sisko, correcting the Defiant's faults and successfully repelling an attack led by Defiant and found the cloaking device had sabotaged the systems on Regent Worf's ship; the Regency-1, and captured both, scoring a massive victory over the Alliance.

In 2375, when Quark and Rom came to the mirror universe with a Klingon-built cloaking device, they were able to escape Terok Nor with the aid of Ezri Tigan and Brunt. Smiley and his rebels pursued in the Defiant. O'Brien, now a general, began to lose favor with the Rebellion in the face of the growing power of fellow Generals' Zek and Bashir. This began when Bashir openly challenged O'Brien's position after allowing Quark and Rom to return to their universe with the cloaking device, which the Rebels could have kept for themselves (despite the fact that the Rebellion had now developed cloaking technology of their own). The situation worsened when he was thought to be going "soft" after starting a romantic relationship with his second-in-command; Commander Keiko Ishikawa.

Demotion
O'Brien was effectively ousted as leader of the Rebellion when he openly ordered the new Empok Nor shipyard shutdown as it was believed to be to easy a target. However, Zek and Bashir planned an attack on Cardassia and Qo'noS and used it sway most Rebel leaders to follow them to the shipyard and use the newly-constructed warships they had made there. Smiley, tipped off (anonymously) by Intendant Ro Laren, alerted Zek and Bashir about an imminent attack on the shipyard but failed to persuade them to turn back. Empok Nor was destroyed along with the warships, most of the Rebels stationed there killed and Zek and Bashir were captured. Smiley initially began to lose hope, but Keiko and his right-hand man; General Michael Eddington, convinced him to rally his troops and continue to lead them to the coming victory over the Alliance.

Further Accounts
Miles would continue to fight "the good fight" for the freedom of the Terran people and their allies. He refused to join the New Terran Empire, because he believed that it would be replacing one tyrant for another.