Why do liberals and neo conservatives not want social issues to become a state/local issue ?

I agree with you about everything. Don't Ask Don't Tell needs to go, and that's coming from Col. Charlie Beckwith for Pete's sake. The Defense of Marriage Act is in principle, unconstitutional and that needs to go as well. Institutionalized racism in the form of racial profiling, affirmative action and hate crime laws need to go as well. Though I do believe the US Army does not screen it's Senior CO's properly, as evidenced by Muslim Terrorist Malik Hasan.