Although the story is a pretty blunt, it made two important statements. First, that Reagan did not arm the Soviet Union to death (a wide-spread myth at that time as well as today), second, that any peace effort is in vain without a little bit of mutual trust. Peace is risky.
I think it doesn't just work as the Cold War analogy it was meant to be, but also as a more general story about war and peace.
Now these are just ideas distilled from the movie, I can understand that you or other folks consider TUC as mediocre, e.g. the whole Gulag / Rura Penthe part is pretty cheesy.