If you're interested in the topic, Frank Rich has an Op-Ed in today's New York Times which does a much more thorough job of destroying the "letting them in will wreck the military" argument.
the most common last-ditch argument for preserving “don’t ask” heard last week, largely from Southern senators, is to protect “troop morale and cohesion.” Every known study says this argument is a canard, as do the real-life examples of the many armies with openly gay troops, including those of Canada, Britain and Israel. But the argument does carry a telling historical pedigree. When Harry Truman ordered the racial integration of the American military in 1948, Congressional opponents (then mainly Southern Democrats) embraced an antediluvian Army prediction from 1940 stating that such a change would threaten national defense by producing “situations destructive to morale.” History will sweep this bogus argument away now as it did then.
And, as for the Rabbis who oppose inclusion on religious and moral grounds? Well, a true refutation of that view would take more time than I have at the moment (because, it's really an ongoing argument against Fundamentalism of any kind), but, for now, a bit of snark will have to do.