Everyone in the crypto currency space presumes that Bitcoin and other P2P protocols create a censorship resistant finanical platform.
It is my opinion, that any PUBLIC P2P network can easily be censored by ISPs. If you can join the network, then you can discover the IP and PORT of every publicly accessible node and then block all packets to/from those nodes on those ports.
Furthermore, every website that hosts content (binaries, source, and seed node IPs) can be shut down in a similar manner.
Even MaidSafe and Tor are not able to prevent this kind of censorship.
Now clearly, it would be difficult to engage in this kind of censorship on a global scale. The end result would be for people to move to VPN systems, which would in turn come under attack because they are "publicly known".
At the end of the day, the great Firewall of China can be applied to any country at any time.
If that were to happen then consensus would have to move to dark networks, on an invite-only basis and the utility of crypto-currencies in general would be dramatically undercut.
In other words, crypto-currencies currently depend upon free speech.
We live in a world where despite the government's best efforts illegal music, movies, and other content manages to survive. What does this tell us? How can centralized services provide us magnet links to torrents with public IPs and those hosts are not shut down?