Frankly, I don't think having gays openly serve in the military significantly affects combat effectiveness, nor do I think a DADT policy makes any sense at all from a security point of view.

Indeed, with regard to the latter, concealing one's sexual identity might be grounds in Canada for denying access to shared US intel material.. how's that for irony? Then again, we have same sex military marriages performed by military chaplains.

More to the point, combat effectiveness does not always trump core issues of human rights. I'm reminded that "combat effectiveness" and unit cohesion was also used as an argument for racial segregation and discrimination in a previous era....