Similar movies?
Of course similar movies would be obvious. All the Godzilla sequels and remakes and all the other Toho Monster and Kaiju movies. But that isn't what I mean. For me those are (for the most part) not similar movies. They are not even the same genre. Those where simply monster and Kaiju movies, with a lot of them even not really being serious, but humorous and sometimes borderline ridiculous and cheesy.
Whereas I feel the original (Japanese version) of Godzilla, wasn't so much a Kaiju or monster film, as it was a serious, sad and sometimes even philosophical movie about the effects of nuclear weapons and mankind's self destructive behavior and stupidity in general.
In most other Godzilla and Kaiju films you don't have such themes anymore. So when I say I am looking for similar films it means I am looking for movies with such grim themes and similar metaphors and symbolism.