It is the best nuclear non proliferation and arms control ad.
But the rest of the film is so apolitical, and so hauntingly well done, that even the "bad guys" in it liked it.
It's really a testament to the film's quality.
I think a point that they were trying to drive home is that there are no "good guys" or winners in a nuclear war, especially when it comes to those who perpetrate it on any side.