> Care to elaborate how it could be done? Either someone puts up an enormous amount of computational power to flood the chain or someone finds a fatal flaw in

> Care to elaborate how it could be done? Either someone puts up an enormous amount of computational power to flood the chain or someone finds a fatal flaw in sha256 and uses that to flood the chain. The former is basically impossible, the latter is just very unlikely. Either way, if someone manages that feat, we can consider Bitcoin practically broken.