Yes, of course, you're totally bang on with your assessment. If there were a serious attack like this I suspect there might be a fork, maybe...
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If you want to perform such an attack regardless of cost, and with unlimited budget, I believe it has already been proven that the Byzantine general's problem is unsolvable, (lacking sufficient incentives)
It's likely that the incentive structure is the only thing that truly protects the blockchain.
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If you want to perform such an attack regardless of cost, and with unlimited budget, I believe it has already been proven that the Byzantine general's problem is unsolvable, (lacking sufficient incentives)
It's likely that the incentive structure is the only thing that truly protects the blockchain.
A fork, sure, but a fork to what? Short of changing the hashing algorithm, I don't see what's going to prevent a destructive miner from shitting all over the new fork, too.
So: double-spends for direct economic gain don't seem likely to be a huge problem. Miners disrupting the network for political reasons (or ransom, for that matter) seems like it could be an issue, but it's hard to estimate how likely such an attack would be.
I don't think you can ever create a currency, which cannot be attacked with sufficient resources. Best we can do, is to create a systems in which attack costs more than gain. Bitcoin has reached that.
