Oh, man. How did I miss the poorly-disguised political ranting when I read this in seventh grade? Heinlein has, like, a fleet of axes to grind. And some horses to beat. And some soapboxes to stack to the sky.
If you can navigate around the creepy paternalistic politics and dehumanization of women and the valorization of a particular brand of masculinity above all else (which you need, like, a supercomputer GPS to dodge), I grudgingly admit that this is a ripping good yarn. I can see why my dad loves this book (which, you know, says a lot about both my dad and the book). It's easy to get swept up in the momentum of the piece, and I always was a sucker for a good training story. Throw in a lot of stuff about teams and struggle and bonding and whatnot, and I kind of enjoy it, when I'm not rolling my eyes at the mockery of namby-pamby twentieth century society filled with people who weren't spanked enough as children. Or whipped as adults.
The most shocking thing of all is how rereading this book gave me a newfound appreciation for the movie. I, like most of the rest of humanity, found the movie nigh-on unwatchable (except for Doogie Howser as the quasi-Nazi psyops guy, which I recognized as hilarious even on first watching). However, in retrospect, I appreciate so many of the changes they made. The military! It's co-ed! And girls get to do things! Not just give men a reason to die! And the entire thing is essentially a piss-take of the hypermilitarized culture that the book venerates! I think it might actually be funny.