> There is a reason that the people with the most aggressive social policies tend to also be the least in favor of federalism/local politics, because of this exact problem: people will just leave.

I don't think that has anything to do with it. Whether people are in favor of or against local politics is mostly based on whether or not they share the same opinions as their local politicians. For example, look at the fight over California Emission standards. People just want to have things their way - everything else is just hot air and posturing.