Fair point. I guess something only like PoS can avoid that problem, if it is infallible, which might not be the case. >The costs of securing conventional centr

Fair point. I guess something only like PoS can avoid that problem, if it is infallible, which might not be the case. >The costs of securing conventional centralized mechanisms (or bank vaults) ramp up much slower than Bitcoin per dollar or per unit of wealth secured. Actually I think the costs are much less, because after a certain point, you're not working to secure the network but racing to make more bitcoin. The network can be secure with much less resources than what is currently being spent. It is a misconception to think that effort to mine is to fight external attacks. It is more like fight between banks to transact faster.