There is only one easy way to compromise the blockchain and that is to compromise one of the witnesses. That can be done by:
- paying them more (yet steem dollar is too small, but will become relevant, when there are steem derivatives)
- blackmailing them (the classic one, witness has sexual quirk and gets filmed during it; possible but steem must be worth a lot because finding out is expensive)
- giving them an ideological reason (Vishnu doesn't like blockchain; possible but unlikely)
- compromising their personal computer system (probably the easiest way with remote controlling the machine)
Would one compromised witness be enough?
lol, o man @ezzy if you ever needed content for a book.