The UCMJ is contained within Title 10 of the USC. It cannot be administratively amended. Moreover, there are many factors that are governed by law. The Services can only amend those things in which discretionary authority is permitted.
Your elected officials are in the driver's seat.
Your elected officials are in the driver's seat. My elected officials are....Osama Hussein Obama,John F'ing Kerry,Scott Brown and Baaaarney Frank.
My understanding is that Brown favors homosexual "marriage".But as an Army officer I don't know his position on DADT.