The money will be worthless regardless of the status of the Fed if we continue to spend like we are. The only reasonable solution is to scale back federal spending to constitutionally supported levels and leave all things not specifically enumerated to the federal government to the states. This will set up a system of competition between the states where people can choose to live in areas that are governed according to the values they espouse.
I like your idea that caters to people that want to live in a certain state. It's brilliant and allows for compromise on the issues if it ever happened.
As for the money, it's already losing value right this second. It's obvious because of our debt ceiling and the billions we borrow from China for our illegal wars. Federal spending does need to pull back, but the first step is to pull out of all these foreign countries. No more Korea, Iraq, Germany, Poland, Afghanistan, Japan, Kuwait, and anything else I missed. People think this is a radical idea, but the truth is the US can defend itself just fine. Dictators like Iran's president just want to left alone and **** their people over. The US's main problem should we pull out on all fronts would be the illegal problem in our southern states.
As for nukes and other attacks, the US has safeguards in place already. Allies like our European countries aren't about to lose their number 1 trading partner. Haarp can be used as a weapon and can deploy to any place on Earth right now. There is just no reason to waste so much money fighting all these illegal wars when our country is in dire straights.