Reading group: Sun and Steel by Yukio Mishima It is not the first time I read that people claim that Japanese society in the context of WWII was 'mediaeval'.
This is a difficult point to explain to a Western person. It was even difficult to understand for me, even though I am very passionate about Mishima.
First, we should not use concepts such as 'mediaeval' because this is a Western notion of the world. If we want to understand Mishima, we have to see Japan from a different view.
Why was Mishima bellicose? Most of his biographers agree that Mishima got a trauma when he was rejected by the Japanese army. At that time, when he was less than 20 years old, he just wanted to serve the country and (probably) had the fetish of dying in the field, like a good samurai. But any of this happened, and his dad (an influential person) forced him to study instead of supporting the army. Mishima never forgot the fact that he was rejected since then, and he starts expressing it through different characters in his novels because, according to him, it is better to die young (youth is equal to purity) and in the army (loyalty) than old in a house (this means dirt, corruption and boredom to him).
Why did Mishima start with physical training and form his own army? I guess he started to feel 'incomplete' with only writing novels, and he wanted to become a 'man of action'.
Honestly, after reading most of his books, I believe he always wanted to die the way he did. He even stated in an interview that he did not expect to live past the age of 50, and he committed suicide at the age of 45. His pursuit was the heroic death that he did not have in WWII, but I believe it is worth noting how he changed over time. From shy novelist to samurai warrior.