I agree that it was a bad adaptation, in that it wasn't particularly faithful to the book, but I didn't like the book all that much; I liked the film a lot better. I think it's often unfairly disregarded as a silly action movie about giant bugs, when it really was a fairly insightful bit of political satire.
I'm still trying to figure out what was insightful about the political satire in the film. I found the over the top and rather unnecessary eeeevilness of the government more comical than the absolutely idiotic action scenes. I mean, you've got giant freakin' insects that annihilated a planet full of humans... some people might consider that a legitimate threat and not have to be bullied/misled/lied to about it for no particularly good reason. Maybe if they got around to exploring what was really going on in the universe (like Ender's Game where the war with the bugs was due to a miscommunication... oops, or covering up the blatant ineptitude of the military or any of a dozen other possibilities) then it would be interesting, but as it was it just showed a bunch of propaganda and a really bad action film. No idea if the propaganda was appropriate or not (Allied vs. Axis propaganda?), but given that the average IQ of characters in the film bordered on freezing ice I gotta think leading these morons around by the nose was necessary. Gotta admit I have the same feeling about the Emperor and the Jedi in episodes 1-3. He was the only competent guy in the universe, seems like putting him in charge isn't such a bad idea.
Course, the fact that the soldiers firearms seemed totally ineffective from more than 5 yards did kind of sour me on Starship Troopers. The scene with a bunch of soldiers standing in a circle and shooting
inward towards a bug decreased my opinion of the intelligence of the filmmakers to the point where I'm not gonna give anything in it the benefit of the doubt. Similar to the problem I have with lightsabers in a blaster fight. Yeah, you can block a shot or 2, but at some point it's just silly. And that point is the colliseum scene in ep 2. In the original trilogy (and even ep 1) they were bright enough to gloss over this and seperate out the lightsaber duels from the shootouts. Honestly, doesn't matter how fancy the knife, it's still a gunfight. Course, the catapult/paintball thing in episode 1 didn't help any. And the
utterly moronic civil war stand in lines and shoot at each other thing in ep 3. Come to think of it, ep 1-3 might have had worse battle scenes than Starship Troopers. Hell, they knew the concept of "taking cover" while on Hoth, guess the clones and robots were just too stupid for that idea to catch hold.
The shower scene in Starship Troopers was interesting. A bunch of totally non-sexual nudity. It was frankly the only "sci-fi" concept I thought done remotely well in the movie. In the future, people are only allowed to have kids after becoming citizens, so casual coed nudity (and one supposes casual sex, not that it's mentioned) among non-citizens isn't such a big deal. No kids will result, and one presumes that STDs aren't that big an issue. One could argue it's postponing the issues of puberty until one becomes a citizen, and get into entire sociological debates about what that would mean. Of course, in this film it was just an excuse to show boobies, but hey, at least it isn't morally repugnant like all those rape scenes in the 70s that they included to sneak shots of boobs in. Or kissing your sister, and later rescuing her while she's wearing a brass bikini and chained to a worm. Or knocking up a Senator and having her die of sadness or some craptastic thing.