thirdly, i think you are taking the word alone out of context. granted its been a while since i have seen the episode but what i took from the meaning was that he wanted ALL federation ships to attack the cardie ships alone (meaning not attacking the dominion ships).
I rather doubt that. We only saw the fighters attacking, no matter what the camera angle. The dialogue never suggested that any other assets took part, either.
I'd also argue that it was an important ingredient in Sisko's plan that those fighters be vulnerable and that many of them die. The Cardassians wouldn't have taken the bait unless they were supremely confident that they could bite the bait's head off with one swift move. Sisko had to bribe them with the deaths of his pilots to get this effect; we heard the Cardassians indicate that they saw through Sisko's plot easily enough, but they took the bait nevertheless because it was such a fat and soft one.
That's classic naval tactics, really. It has always been useful to have expendable assets to harass the enemy, and entire doctrines and shipbuilding programs have been based on the idea that there would be ship types whose principal function was to die hopelessly outmatched by the enemy.
It's murder all right, in the sense of being premeditated killing. Not in the sense of being premeditated
illegal killing, though, as every general (and even a lowly colonel/captain like Sisko) has the legal mandate. And it saves lives elsewhere - more important lives, lives aboard one's capital ships, and perhaps ultimately civilian lives that would otherwise be lost if the enemy carried the day.
Timo Saloniemi