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Someone further down the thread also mentioned a very good point in that the attackers could potentially start a bidding war against such a fork. They would have nothing to lose compared to a situation where the heist is reversed.

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They have a fairly elegant mechanism to do so, too: just chain transactions from T to the addresses the miners send their coinbase transactions to. If miners go forward with the re-write history plan, the bribe gets undelivered, Back to the Future style.

It might be one of the first cases of bribery where the briber doesn't have to talk to the bribee to discuss the object of the conspiracy, the price, or how the bribe would be delivered.

Amazing.

Oh it gets better! The attackers can do things like entangle their stolen Bitcoin in systemically important institutions. Say, send 0.01 BTC to Coinbase. Coinbase is probably not operationally capable of separation that Bad Bitcoin from their Good Bitcoin before it's been comingled with customer funds. At that point, reversing T would also invalidate consequential transactions by Coinbase, which is probably something they can't allow to happen, so they would pay miners to not reverse.

Comedy. Gold!

It sounds like miners could find a replacement revenue stream even if block rewards go to zero and transaction fees are low: Hold the blockchain hostage for reversal and sell out to the highest bidder!

(Of course, this would likely drive the value of 1 BTC to exactly $0)

(Edit: This is all a demonstration of how the security of the blockchain absolutely depends on mining hashpower being widely decentralized and distributed)

Which is one of the more practical reasons a rollback is very, very unlikely to happen. (It would have been fairly unlikely even in the case of ethereum/theDAO, had not the nature of that exploit effectively locked the funds for a month.)

Schelling-point bribery

Kinda reminds me of Eliezer's concept of acausal blackmail

What happens to people/exchanges that had already accepted stolen cryptocoin after such "justice forks"?

In that new valid blockchain, the transaction where they were given that coin will simply not be there.

I'm not 100% sure but I think that anyone can re-submit the "undone" transaction to the new blockchain, as long as the source address hasn't already spent its balance on the new chain? Isn't this what's called a "replay"?

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