"So you're telling me that in order to fight the Reds you have to be ready to do anything, including adopting their methods. It seems to me that it's pretty hard to tell one dictatorship from another."

It's true that free societies and totalitarian/authoritarian societies adopt many of the same lethal or even ruthless methods during a war. A good case can be made that the Allies were even harder on civilian populations than the Axis powers, although this was more from lack of opportunity than any restraint.

The difference is motivation, something critical in modern wars that has eluded a lot of people. A crystalline certainty at the heart of the Middle East conflict is that if the Arabs stopped attacking and killing, there would be peace. Is the reverse true?

Also, it should be noted, when the war is over, a free society goes back to being a free society. The others remain thugs.

...Then, once more, the bell-like chiming sounded, and the seated, stony figure of Yarnek emerged from its cocoon of rainbows.

"You are the survivors," the echoing voice said. "The others have run off. It would appear that evil retreats when forcibly confronted. However, you have failed to demonstrate to me any other difference between your philosophies. Your good and your evil use the same methods, achieve the same results. Do you have an explanation?"

"You established the methods and the goals," Kirk said.

"For you to use as you chose."

"What did you offer them if they won?"

"What they wanted most—power."

"You offered me the lives of my crew."

"I perceive," Yarnak said. "You have won their lives."

--From the Star Trek episode, “The Savage Curtain,” adapted by James Blish.