the air force is willing to move people with lgbtq kids to bases in states that don't have repressive laws. that may not be "progressive" but it's a lot better than they would have done in the 50s or even the 90s
and are we really "maintaining imperial dominance" ? what exactly comprises the "empire" ?...would you have us ignore pleas from help from allies, because we wouldn't want to be perceived as empire builders?
of course if cultural norms hadn't changed they would not have become accepting of lgbtq people, that's true of everything that has changed, ever, in every society...but they did change, and the different branches of the armed forces have adopted those changes at different rates. the air force seems the most willing to adapt and adopt, the navy only slightly less so, while the army is far behind, and the marines behind the army. the armed forces exist, and at least some parts of it are ok with people being what they are, that's a vast improvement to the situation as little as 20 years ago