Despite being a hardcore Roddenberryian I am fine with Sisko turning a blind eye to Garak doing some nasty stuff for him to get the Rommies into the war.
Sisko bribed Quark and allowed Garak to kill some people. The distinction between looking away and doing it yourself might seem trivial but I don't think it is. At least I would have a problem with Sisko's actions if he had done all of Garak's dirty work himself. We all know the trolley problem so I know that it is not rational, doing it yourself or allowing somebody to do something which you don't wanna yet admit to yourself but basically know boils down to the same thing. It is irrational but feels right to me.