I don't believe the U.S. Military (at the very least) addresses females as "sir".
LOL... and if you get a really touchy female officer who is called 'Sir', she might even press charges agianst you! It is considered the WORST of military manners to refer to a female officer as 'Sir.'
It does make a certain amount of sense for a military or police organization to use a 'every officer is sir' protocol, however, and it has nothing to do with political correctness. It's more of 'an officer is an officer' kind of thing, which, if you're in uniform, is exactly the case. Women may be different from men, but the police officer telling you to drop your weapon or the Lieutenant Colonel giving you an order should probably be addressed based on their occupational role, not their gender.
Sorry, but it's insulting.
I'm being ABSOLUTELY no less respectful to her position calling a female teacher 'M'am' instead of the neutral 'Doctor' (if she has a PhD).
I'm being ABSOLUTELY no less respectful to her position calling future (she gets it at the end of this semester) 2nd Lt. Langdern 'M'am' instead of the neutral 'Leutenant' or the masculine 'Sir.' In fact, Langdern is pretty well-built (muscular) and would really take it as a slight if someone addressed her that way. In fact, so would ALL the female officers, enlisted soldiers and cadets I know- including the gay one.
It's shameful that people try and wipe out the fact that they are women. if you think that they have had to work through discrimination and inequality to get where they are, wouldn't addressing them as 'M'am' actually be a mark of accomplishment? Wouldn't it be more of a badge of honor than 'Sir,' seeing as how 'M'am' is a more hard-won title?
Why take away that accomplishment?
Equality is in what they do with their position, not in how you address them!