Heinlein is one of my favorite authors. Starship Troopers the movie didn't do full justice to the book of course. I actually would prefer a society like that, over what I live in now. I don't consider it fascist.
I consider what we have now in the USA to be FAR more Fascist than Starship Troopers. Although the USA isn't 'Nationalist' any more, as it has become a Marxist utopia heading for Bolshevik Revolution. Like a twisted mix of Fascism with Marxism.

The 'DeafPhoenician' of 'Fascism' is quite varying depending on the source.

Fascism