The Evasions of Robert McNamara - What's true and what's a lie in The Fog of War? By Fred Kaplan
"McNamara puts it this way:
"'LeMay said, "If we'd lost the war, we'd all have been prosecuted as war criminals." And I think he's right. He—and, I'd say, I—were behaving as war criminals. LeMay recognized that what he was doing would be thought immoral if his side had lost. But what makes it immoral if you lose and not immoral if you win?'"
Well....remembering our just war theory...violence can only be employed proportionally, and part of proportionality is probability of sucess. Suceeding tends to suggest that the probability of sucess was high (yes, statisticians, this is not strict implicature). Thus, winning suggests that the means were more likely to have been moral than losing while using the same means.