But didnt you see that Walmart itself will be forced onto the fake chain due to the inevitable forces of entropy? Surely, they wont have 100% uptime, so their server will need to be restarted and murphy's law GUARANTEES that they will lose not just the local copy of the blockchain, but absolutely all backups. And inevitably as surely as day follows night, they will connect to the attacker's node and sync to the fake history where their balance is zero.

However, there is at the same time a mass hypnosis spell being cast on all data center operators, so they dont notice they have a zero balance and then the critical Walmart nodes are now part of the attacker's network. And it is unstoppable, after Walmart, all the other companies realize that they too are on the wrong network and immediately switch to the attacker's network. Management is useless as they dont understand the tech at all and just writeoff all the lost funds as a business expense. None of the customers impacted by this make a single complaint so it is impossible for anybody at all to notice something is wrong. And thus the attacker's network is 100% guaranteed to takeover completely. The exact time for this is not possible to know, but typically it would happen within a few hours, maybe 10 hours at most, so dont talk about any 720 block thing.

And there is no point to say that any single assumption in the above is unlikely to happen. It will happen, this is by assertion. So it must happen and therefore the above is not unlikely at all. How can you say that any of the above is unlikely when it is assumed that it would happen?

James