>Might does not make right in questions of rule of law
Sure it does. The laws are written by those who can enforce them. That is by definition those with Might. If that is barbarism then all of earth is under barbarism (and I'd argue that this is true).
History is full of good examples. The Nuremberg trials is a great example of Might Is Right. The exact same laws used against the Nazis never were enforced on US citizens.
Rule of law does not have baked into it that laws are written by the mighty, or even that they can or will be enforced, consistently or otherwise. Merely that laws exist, can be made, and unmade, and should be followed.
After all, there was a reason the Founders advised that it was a great evil to put a law on the books that couldn't be reasonably enforced due to the tendency to deligitimize the authority in question.
Unless it's barbarism then. At that point I'm pretty sure the biggest functional nuclear stockpile wins though.