Heinlein liked to turn sociopolitical thought experiments into novels. Stranger in a Strange Land was published a year and a half after Starship Troopers. If you're not familiar, it's basically about starting a massively successful free-love commune religion. The Moon is a Harsh Mistress, five years later, is about a libertarian (arguably anarchic, by some definitions) revolution for independence.

I think any attribution of advocacy for any of the political ideologies expressed in his books, even when vindicated by the narrative, misses the point a bit. It seems much more likely that he was exploring various political ideas through the narrative form.

Kinda like this post about The Twilight Zone: