You can't rewrite the history of blocks that have already been distributed. You may fool SPV nodes but any node with a copy of the blockchain (even if pruned) will reject your version.
This is false. Please read the white paper. It clearly states in section 4:
> The majority decision is represented by the longest chain, which has the greatest proof-of-work effort invested in it. If a majority of CPU power is controlled by honest nodes, the honest chain will grow the fastest and outpace any competing chains.
If the majority of the hashpower (not nodes!) is dishonest, you can rewrite history. It's the reason why the current difficulty is part of a block.
This has been done numerous times in the past for small but highly traded altcoins.
> The majority decision is represented by the longest chain, which has the greatest proof-of-work effort invested in it. If a majority of CPU power is controlled by honest nodes, the honest chain will grow the fastest and outpace any competing chains.
If the majority of the hashpower (not nodes!) is dishonest, you can rewrite history. It's the reason why the current difficulty is part of a block.
This has been done numerous times in the past for small but highly traded altcoins.