Quote from: Wipeout2097 on October 01, 2013, 10:26:56 AM

Quick question: can or cannot a powerful actor, like an opressive government compromise bitcoin? For example, run multiple rogue bitcoin full nodes and modifying source code according to their best interest. What is the worst that can happen?

Thanks.

the worst case is that the USG or some other large-scale actor has ASICs that can beat the shit out of everything created publicly thus far. in this case they can rewrite, i.e. spoof, the entire blockchain since the last checkpoint. however, this is highly unlikely and would blow their cover since there is no plausibly deniable story for what happened besides "we decided to take over your chain, dawg". i know some ppl have a distaste for checkpoints, but i think they are a good idea.

as i stated above, such an attack would be rather overt and would likely tip the hand of an attacker. once you know someone knows, you know you need to adjust your behavior (hawthorne effect). lesser attacks would be 51% attacks but these suffer from the same hawthorne effect mechanism i just referenced.

overall, the system is quite secure unless a large group with advanced crypto knowledge, tons of money and serious hw chops were to openly attempt to shut it down.