To the OP (FM), it's a fricking awesome movie...that's why you like it. It's the epirome of a mindless, over-the-top blockbuster-type movie. Everything is overdone on purpose, even the acting IMO (though there aren't "great" actors in it). It has blood, guts, violence, sex, tits, cheesiness, etc...it's a shitpile of awesome. The only thing it really went easy on was the language.
It works on this level, because Verhooven, man. But it's also a pretty brilliant satire that you don't even need to realize is happening for the movie to work because -- HEY! Blood and boobs!
But the movie is essentially a thorough deconstruction of Heinlein's book, exposing it for the awful Nazi-worshiping piece of trash it is. The book is not as overt in its fascist references, but Verhooven pulls them out and shows the humans as the villains the story, and they are the fanatical fascist state. It's a throwaway line, but it's worth noting the humans started the war, not the bugs.
I think he intentionally used pretty, young, dumb actors to show how people buy into propaganda and get chewed up by it. About the only person in the film aware its a satire is NPH. A self-aware performance by the leads might have ruined it. It's why Denise Richards bad line reading is so perfect. She is brainless.
Man, I love this movie.