One possibility involves the presence of a university which would be a source of jobs and income for many in the community. Some small Catholic colleges in relatively rural areas have seen this kind of thing flourish spontaneously. But I think the key is that the community should arise on its own; the planned community of Ave Maria in Florida seems like something that could easily be a disappointment to those who choose to settle there, for reasons that are beyond the scope of a single blog entry.If you follow the link you can see a few obvious drawbacks at Ave Maria: they've already contracted with the Publix supermarket chain and BP. Since these businesses market goods from the godless outside world, there's always a possibility that residents may find the near occasion of sin in a sexy magazine or tomato can label. And isn't consumerism part of the problem? Won't the bounty of big-time supermarket shelves corrupt the souls of the anointed?
For centuries "autonomous" communities sustained themselves -- and some monks, zealots, and survivalists still do. Why can't the Crunchies till the land, bake bread, fetch water, and read the Bible by candlelight, if this is what the Lord has called them to do?
The obvious answer is they don't really want to. From comments on this post, and the blog generally, there seem to be an awful lot of Crunchies who expect to keep a desk job in the New Jerusalem.
I look forward to the day when some fundamentalist billionaire gifts Dreher and his crew with some arable land. Within weeks there'll be big fights around the Talking Stick, as public relations executives and journalists explain why someone else should hammer nails. Eventually Dreher will have to announce that an angel has told him the location of some magic tablets or something. And the great thing is, there'll be plenty of knowledge workers on hand to document the collapse.
UPDATE. Commenter FMguru reminds us that "the traditional conservative Christian way to deal with this problem is to import menial labor from far away, transported in the packed, sweltering cargo holds of specially-built sailing ships."