Star Trek: Deep Space Nine showed a Starfleet captain go beyond the actions of many, and actively rejected many Starfleet directives in an attempt to win a war.
Star Trek: Deep Space Nine showed arguably the most morally grey captain in the show’s history. During the show, Captain Benjamin Sisko was placed at an outpost near the edge of Federation space with the daunting task of ushering the Bjorans into the Federation. This as wounds were still festering after the Occupation of Bajor by the Cardassians. If that task wasn’t hard enough, Sisko was then thrust into a war between not just the Dominion and the Alpha Quadrant but the Pah Wraiths and Prophets of the Bajoran Wormhole.
Oh, and Sisko had to deal with Bajoran terrorists who really liked Les Miserable.
Considering all that Sisko had to put up with, you can’t really argue that some of his more intense actions weren’t justified. That said, Sisko blackmailed Quark, dated a smuggler for the Maquis, then arrested her, poisoned an entire planet to drive said Maquis off-planet and then aligned himself with a foreign spy in an attempt to bring the Romulans into the war.
That alignment started with a minor war crime, and ended with a major one. Sisko went to Cardassian spy Elim Garak in an attempt to doctor a video that would show the Dominion and its allies preparing to betray the Romulans. Garak assured Sisko the forgery would look convincing but the Romulans still figured out it was a fake. With the Romulans heading back to Romulus, a bomb went off, killing the small delegation sent to meet with Sisko. Garak was revealed to have been the saboteur, and even revealed to Sisko that the doctored tape was never going to work. Something Garak accused Sisko of being subconsciously aware of, which is why he came to Garak in the first place. To do the things he wouldn’t do himself.
While he doesn’t have any blood on his hands after the assassination, Sisko opted to keep the information to himself, rather than lose their new allies.
One could argue all of these decisions, and all of the other slightly shady things Sisko did, were all necessary. That without these moves and decisions the Cardassians would have retaken Bajor and the Dominion would have eventually taken the Alpha Quadrant. One could also argue that there may have been a better way. So do you support the actions of Sisko?