1) Barracks situation: Marines live two to three to a room. Marines have generally produced reservations of undressing in front of gay men. In light of the general concern, he has stated that he will not force Marines to live under conditions that he is "very" opposed to. The general civilian public will reply with "suck it up" or "get out." In the end, the civilian public can't afford for thousands to simply "get out." Therefore, concerns must be met with solutions other than the troop supporting retort of "**** you" by the average American who supports his mission to kill for him, but not his support on personal opinion or belief.
2) Showering situations: Marines and Naval personell shower in groups consistenly in deployed situations. Traditionally this has been separated between dicks and vaginas. However, things have changed. Sexual orientation is a concern of the average Marine. All it takes is one asshole to point out a "fag" to wreck unit cohesion.
Which brings me to a third general concern amongst Marines...
3) Unit cohesion: This is very important to Marines, especially. We are what we are because of unit cohesion and brotherhood. Sexual wierdness and tension has no place in a combat unit, which is a a factor in regards to where women don't belong. It breeds unnecesary competition in a "Fire Team." Furthermore, new Marines who are identified as "gays in the shower" or "boyfriends in the room" divide what should be a single muscle.
What I get is how the jack-ass crowd on one side insists that the Hollywood stereotype of what a gay is is what the military is about to get. It's thrown in their face constantly. Anybody seen an episode of "Will and Grace" lately? But what I don't get is how the gay rights parade insists on equality, but then denounce that gays are sexual beings like the rest of us. There will be problems. And this is what the Pentagon Study is figuring out.