I don't get all these "it's something more than military" comments. Everything we've seen Starfleet do is consistent with what militaries today have done. Granted, Starfleet might have a larger science division than any military organization, but they operate in space. Space has all kinds of weird shit that is going to require you to have scientists on your ships, and likewise you're going to want to study this stuff and research it for any practical advantages it offers. This is consistent among Trek's militristic aliens like the Klingons and Romulans, why would Starfleet be any less of a military because of it?
Starfleet is the military, it was very clearly depicted as one in TOS. I say it still was in the 24th century, and that the times people said it wasn't is a relfection of propaganda. People sign up for Starfleet so that they can hang out on paradise planets and score with the local women with many breasts, amazing looks, and open minded about -ah screw it, they want to bang alien women, okay? What they don't sign up for is to get stuck on some filthy rock fighting scaly gray skin aliens over some communications outpost, even if that's what they end up doing.