It's great to finally see people treating the US military's "don't ask - don't tell" nonsense as the irrational woo that it is. The other night Colin Powell and Clifford Alexander separately addressed this issue on Rachel Maddow, and I thought Alexander in particular laid out the despicable illogic of the military's standing position.
I'm not a military specialist, so I can't address that side of this issue. But I do think this whole issue of gays in the military should be assessed empirically, once and for all. Put simply, is there a valid, objective and quantifiable negative effect on readiness and unit effectiveness, of openly-serving gay military personnel? This is a question that is addressable with data, not dogma.
If I understand the argument against gays in the military, the major premise assumes that openly-gay soldiers are somehow corrosive to unit readiness. In what way, though, is such corrosion engendered? There are really only two options: disruption caused by the gays themselves, or by the reactions of straights to them.
In the former case, what is the feared disruption? Sexual predation, or inappropriate on-duty behavior? Okay then, if that is the hypothesis, then it is testable. Do gay service members exhibit higher frequencies of inappropriate sexual aggression or lewd behavior toward others while in a professional working context? Either they do or they don't, statistically speaking. This is measurable. An analysis of frequencies of inappropriate professional behavior stemming from sexual motivations in other contexts (corporate professional, public schools, military units in nations that don't discriminate) should be able to settle this issue. Many other nations have integrated their military services with respect to gay people, and one could look at their records. If those data show no intrinsic problems associated specifically with gays, the hypothesis fails.
Another option would be disruption caused by the reactions of straight soldiers to gays. Do straights get freaked out around gays, in other words. If so, this is a discipline problem with straight service-people, not an innate problem that arises from gay people themselves. I wouldn't be surprised if this were the case, actually. I grew up in a rural setting in the Deep South, where reflexive prejudice was the assumed default position for most questions involving people unlike yourself. If the only reason to keep gays out of the military is to appease the delicate sensibilities of homophobic bigots, that's a pretty weak position to defend.
In fact I'd argue that would be an excellent reason to do away with DADT... because it would force people from cloistered, sheltered upbringings to quickly adapt to a polyglot world. At first, racial integration of the military was controversial, until soldiers were forced to work alongside people of other races and white soldiers were told to keep to their work instead of harassing the black guys. Eventually things worked out, and now black and white soldiers work and fight efficiently alongside each other. Bigots still enter the service, but they have to learn to swallow their bigotry or else they are discharged. I imagine quite a few rural whites leave the military less bigoted than when they went in, with respect to their views on other races. If that assessment is realistic, it's likely that having openly-serving gays in the military could do a lot of good, with respect to general public sentiments regarding gays as a minority.
Do military leaders fear inappropriate sexual relations between service-people, if gays are admitted openly? If so, why do they fear this? It's already against military regulations for soldiers to have sexual relationships with their direct superiors, and presumably that would apply to either gay or straight couples. Are there regulations against male and female soldiers in the same unit dating? If so, simply apply that rule to gay relationships. Is it a breech of military law for male soldiers to gang rape female soldiers? If so, simply apply that rule to gay interactions, too.
If the source of problems associated with gays in the military stem from bigotry, that's easy to fix. Simply tell the soldiers to shape up, act like professionals, and do their jobs. I'm sure they're capable of that.