But if it is an enclave and closed, and the...re are known
  consequences (carried out faithfully) - then there will be a
  "forced cooperation" - sort of like marriage in the days/areas
  of the world where divorce was not an option. A nasty example to
  be sure... but it's in the same family of ideas. I'm sure there
  are better models - I know you're not sticking exclus... "