Assuming the total computation power of the swarm is constant, it would take a 100% majority a year to rewrite a law that was passed a year ago. It would also be relativly easy to detect (noticing that you just resolved a gigantic fork, or that the law just changed), and easy to prove, as someone with a copy of the old blockchain could still prove it has a years worth of work on it.
Once this is done, you can explicitly blacklist the offending chain and get on with life.
Comments
Assuming the total computation power of the swarm is constant, it would take a 100% majority a year to rewrite a law that was passed a year ago. It would also be relativly easy to detect (noticing that you just resolved a gigantic fork, or that the law just changed), and easy to prove, as someone with a copy of the old blockchain could still prove it has a years worth of work on it.
Once this is done, you can explicitly blacklist the offending chain and get on with life.
For some reason, I am suddenly finding myself imagining the island of Paxos.
(For anyone who isn't familiar with the reference, here's a primer: https://plus.google.com/+YonatanZunger/posts/ZZ9wDbLDr3A )