How would tax and government revenue be enforced in a bitcoin run society?
It is a PUBLIC LEDGER - anyone can follow an address trail, and the governments of the world already know how to do that - and that is why so many are looking to adopt Bitcoin and make their own digital currencies.  See especially https://secure.caseyresearch.com/chain?cid=MKT336710&amp;eid=MKT337276&amp;encryptedSnaid=&amp;snaid=&amp;step=start