Anarchy: Well, I think you'll find those became real problems during the nineties.
Furthermore, many of the pressure groups in the Democrats are distinctly anti-military. Affirmative action certainly isn't a Republican thing. The Republicans can be blamed for a lot of things, but not that.
I think also part of the reason they're seen as isolated incidents is for exactly the same reason that most (if not all...I can't remember) of the people writing those letters to Fred wished to remain annonymous. It's the kiss of death to speak out on it if you're in a military career, because the military is controlled by politicians and lobby groups.
There may be exceptions to the rule, but generally speaking, few women are going to be able to keep pace with your average military guy. Not only that, but many don't even want to try. Everyone knows this, but no one wants to say it for fear of never being promoted again, or worse. That's why these are "isolated" incidents. I bet if you could confidentially interview most men in the forces or who have recently left, you'd hear it time and again.