I hadn't heard of Mishima before this, but I did get the distinct impression from reading that article that they were lionizing a fascist.
Well, he's a good writer, but he was definitely a fascist. There's probably a bit of wiggle room in the difference between japanese and european fascism, but he's pretty solidly in the japanese fascist tradition.
I have to admit that this "last man" stuff rings of the "soyboy" rhetoric you hear in some corners of the web.
I don't think he's mainstreamed there, but he definitely has a growing fanbase on the Anglophone internet.