It's quite a film, and must have been rather daring when it was released in 1959. Instead of laying blame on a specific superpower, the film is more a general cautionary note against the nuclear arms race. Apparently, this was still too radical for some during the height of the Cold War. The New York Daily News took a swipe at the film in it's review:
"This is a would-be shocker which plays right up the alley of a) the Kremlin and b) the Western defeatists and/or traitors who yelp for the scrapping of the H-bomb. ... See this picture if you must (it seems bound to be much talked about), but keep in mind that the thinking it represents points the way toward eventual Communist enslavement of the entire human race."Reading this was reassuring in a way. It shows that the language of the radical and dangerous right wing hasn't changed a hell of a lot in almost fifty years. It makes the shmucks easier to spot.