Bitcoin security expert: Although a 51% attack can occur, it is inaccurate for an attacker to change the entire chain

Bitcoin security expert Andreas Antonopoulos said that although a 51% attack can occur, it is inaccurate for an attacker to change the entire chain. The situation where an attacker can "make the transaction disappear" applies only to the nearest chain, up to six blocks, which is why the platform has 6 confirmations before approving the transaction. A 51% attack cannot "change the rules" either, other nodes will simply reject them. This, in turn, will result in a hard fork, creating altcoins that no one will accept.