Quote from: jfhoff on April 15, 2013, 05:21:55 PM

This kind of attack, by a central bank or a large government, is the one that worries me. Even though such an attack requires a "HUGE" amount of computing power, it would be trivial for a large, threatened institution that is concerned, not in turning a buck, but in destroying BTC.

I would think most governments realize the futility of this. I mean the destruction of napster killed file sharing right? Also unlike napster no government has made virtual currencies illegal. Lots of US citizens for example hold legal Bitcoins, the US government willfilly destroying legal property of its own citizens would be ground for a lawsuit against the government. Also no government is an island unto itself. There would be international legal and foreign policy fallout. If citizens in other countries lost funds there could be trade retaliation, demands for compensation, etc.

Now someone might naively think the US government could keep this a secret but really look at recent US screw ups ("Benghazi" anyone) and all the embaressing details which leaked out.

Still in theory it could happen however it would simply push crypto-currency into other methods of securing the blockchain like POW & POS hybrids or even more advanced concepts like proof of history (strongly signed miners), etc. One could even take the existing blockchain prior to the attack and use it as the genesis block to bootstrap a new crypto-currency with hundreds of thousands of users on day 0.

It could happen but I don't lose much sleep over it.