Looks like they'll have to formulate a new excuse, because the "unit cohesion" argument does not seem to hold (that is the same excuse they used to keep females out, fwiw, as well).
http://www.navytimes.com/story.php?f=1-292925-1164761.phpResistance to serving in the military alongside openly gay people may not be as strong as expected.
Lifting the Defense Department ban on service by openly gay service members would have no effect on the decision to enlist of 76 percent of those questioned in a new survey released Monday. The survey was commissioned by the Center for the Study of Sexual Minorities in the Military, a research institute affiliated with the University of California, Santa Barbara.
Twenty-one percent of those surveyed said the presence of openly gay service members would deter their service, and 2 percent said they would be more likely to join the military if openly gay service members were allowed.
Aaron Belkin, the research institute’s director, said the survey “may cast some doubt” on the argument that having opening gay service members would hurt morale and deter enlistment.
~~~more at link~~~