Yukio Mishima
Mishima did not serve in the Japanese forces because he was young (around 19 and 20 years) and an intellectual ready to fulfil his life with literature. I guess his disappointment with
modern Japanese society has a lot of points to consider of.
When Japan loses WWII starts a period of lack of confidence on "Japanese values" because they noticed that they weren't good enough to win the war. Since 1945, the new Japanese citizens started to be more
Westerly. They use smoking instead kimono. The women are independent instead of being surrounded by Men. Samurai are no longer respectful and Japan became an economical potency without their roots and values.
In this precisely moment Mishima wonders if Japan would disappear if they give up their values and history because the modern society doesn't seem to look like the previous one of WWII. He did his best to re-establish the respect to the emperor and make Japan a country of samurai not entrepreneurs.
When he perceived that nobody didn't care that much as expected he ended his life with
seppuku.
But it is important to highlight that for Mishima (and other Japanese artists) suicide is a beautiful ending. It is not perceived as bad as Westerns.
The Japanese have always been a people with a severe awareness of death. But the Japanese concept of death is pure and clear, and in that sense it is different from death as something disgusting and terrible as it is perceived by Westerners. — Yukio Mishima