"I think, if they were trying to overthrow Versailles merely, they would have just declare it null"
And with that, Thucydides is unmuted (I'm glad I saw that before I logged in). Welcome back to Earth, Thucy.
And indeed, why not simply repudiate Versailles? If Germany believed that the Entente was incapable of attacking in the defense of Poland, they should also believe that they were incapable of attacking to support Versailles.
Anyway, getting back to the original question, if I understand correctly, phil_a_s has the position that there is always a wrong side, but declares that "I don't think there is an objective way to measure it compatible with my moral values, so I made it one of them."
So is the answer to the question "No, one side is always wrong, but we take this as an axiom"?