Then how do we account for the (I think it is the) Dutch Army? They have gays serving, and apparently not all the problems you mention.
First, there is really no comparison since the Dutch Army is nowhere near the fighting force as the US military. Not even in the same ballpark. Not even the same sport. This gives them the leeway to care about things like sexual liberation in a military setting. There is no concern for loss over combat effectiveness since the Dutch Army has no real combat effectiveness to begin with, and is only playing a minor part in Afghanistan, and no part in Iraq. They have the leisure to care about the feelings of homosexuals. The US military does not.
Second, the social attitude of the Netherlands are not the same as the US. And thus the attitude of their soldiers are not the same as US soldiers. In addition, I would doubt they have the same, shall we say...zeal, for litigation and political correctness that the US does. I'm skeptical that a pornographic magazine in the possession of a Dutch soldier, or the telling of an off-color joke would be grounds for a Dutch soldier to lose pay or be reduced in rank. However, both are very real concerns in the US military.
Let's put this in perspective. We are currently engaged in a war in Afghanistan, and the withdraw from a past war in Iraq. Combat operations with real shooting and real killing are going on every day. And yet, we have Majors and Colonels who do nothing but make sure soldiers are wearing their reflective safety belts while on the FOB/COB, write up soldiers for being dirty and unkempt at the chow hall (even if just returned from an 18hr mission), issue speeding tickets for driving HMMWVs faster than a walking pace on post or without a ground guide, issue Article 15s to soldiers who's wives or girlfriends send the scantily clad photos, give negative counseling statements to soldiers who have untucked PT shirts, or are wearing PT shirts with civilian shorts, or black socks while in PT gear, and quite frankly millions of other little things that basically serve no real combat purpose. Now you can argue, with no small degree of truth, that all of these things promote discipline, which does in turn help combat effectiveness. But that isn't the point. The point is, that even for soldiers engaged in real combat in a war, they still have a book of rules a foot thick to think about and follow, as well as a host of other Equal Opportunity concerns telling them what to say, what they can read, what websites they can go to, what jokes they can tell, and so on. A US military member engaged in combat in the war in Afghanistan does
not need yet another level of social engineering and childish behavior rules foisted on top of the crap they already have to worry about, in addition to their actual mission.
I'm sorry that some people have their feelings hurt about this issue. But we're in a war. Your feelings don't matter.