But the whole point I am making is that laws and treaties are the "CHILD" of morality and ethics. Absent some appeal to a higher morality/ethical standard, the laws or treaties are meaningless. Without some higher standard against which all behaviors are measured, you are left with nothing more than G. J. Caesar's dictum about the victors doing whatever they want and the defeated enduring whatever the victor wishes (a.k.a. might makes right).
While it does matter how/by whom the borders were established in terms of levels of practical support etc., you are absolutely correct as to the illegality of Russia's annexation of Crimea. Russia broke the treaty signed with Ukraine, with the "plebiscite" for an Crimean 'anschluss' with Russia being blatantly inappropriate by all accepted international standards and an abrogation of the treaty signed with Crimea.
What I have been arguing is that applying the old classic "all have been immoral in the past" standard to undercut the "morality score" of any international actor, implicitly undercuts the spirit of the entirety of international law. Without some appeal to a higher, generally accepted ethical standard, you devolve to old fashioned might-makes-right sensibilities. By that old bronze-age standard, the Russians have a RIGHT to the Crimea because Ukraine isn't powerful enough to do shit to stop it.
With a higher standard of accepted practices in place, then other nations MUST work to redress the issue, and not acknowledge it and support it, because that kind of annexation despite treaty and under questionable plebiscite support is not condoned by UN era standards of ethical behavior among nations.
I do note however, that the West's collective response has been pretty anemic. It should have been handled in much the same manner as was the annexation of Kuwait in 1991. And yes, that does mean facing down a nation armed with nuclear weapons by asserting that any resort to those weapons will bring about a collective response in kind by the coalition opposing the annexation. You cannot bluff with this kind of stuff, it must be credible. The West's unwillingness to take this step has allowed Russian to use Caesar's approach.
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