Glad to see folks thinking ahead!  As a lawyer, I'm less concerned about the legal issues you raise and more concerned about the security issues, perhaps because my grasp of the latter is wanting.

Legally, state censorship of Steemit would be incredibly difficult, at least once it reaches sufficient scale.  Judges cannot order individuals to do things beyond their control.  For instance, a judge cannot legally order me to paint the sky red.  And, reversing entries on a sufficiently secure blockchain is the rough digital equivalent of painting the sky red.  To the extent that such a reversal is possible at all, it could only be done by a large group of people (called "witnesses" in the Steemit system, I think) acting in concert.  Provided that this group is sufficiently large and sufficiently distributed across multiple legal jurisdictions, successful state censorship becomes very, very unlikely.  

It's also unlikely that a judge (in the US at least) could compel a person to write code.  Code is speech, and speech is Constitutionally protected.  So, targeting developers probably isn't a winning strategy for the state either.     

Nonetheless there will be community policing and community censorship to some degree via the down voting process.  It will be fascinating to see how that works and evolves.  I imagine that organizations like ISIS would get down voted to irrelevance, but perhaps not.  And perhaps they can find ways of gaming the system to work in their favor.