10 Star Trek Assassinations That Changed Everything
8. Vreenek
...all it cost was the life of one Romulan Senator, one criminal, and the self-respect of one Starfleet officer. I don't know about you, but I'd call that a bargain.
The Senator to which Garak was referring was Vreenek, one of the fiercest advocates for the Romulan non-aggression pact with the Dominion. After luring him to Deep Space Nine, Garak snuck aboard his shuttle, planted a bomb, and set the stage for the end of said pact.
Sisko may have been furious, at least on the surface, to discover he had been an accessory to murder, but consider the result. The Romulan Empire joined the war effort against the Dominion, striking back at bases along the border, and helping to bolster the Federation Alliance Forces.
The methods of War are shrouded in shades of grey, and there is no question that Vreenek's death broke many of the sacred laws of Starfleet. When law stands in the way - outsource. Garak was right, that was why Sisko had come to him. It may not have been overtly conscious, but none but Garak had the fortitude to pull it off.