Right, so you threaten all of them with jail until they hand over the keys to a US Court to continue to do the takedowns for copyright enforcement / ISIS website / scam site pretending to be Amazon / the new Silk Road / $reason.

We have seen this before, where people who run these services are personally held in contempt until they comply with the order.

There are no "people who run these services" in the case of blockchain name resolution, though. There is (usually) a single person who possesses the private key necessary to update the records for a domain - if they find out who that is, they're welcome to use legal compulsion to force them to act.

* I say "usually" because more complex permissions schemes are possible with Bitcoin Script. m-of-n in particular I could see being very useful; it could allow individuals to update some parts of the record but not all - for instance, make it mathematically impossible to abandon the domain or move where it's pointed, but still possible to update contact information.

This is exactly the reason that peer-to-peer services never work. Tor, BitTorrent, cryptocurrency: Failures, all. Each of their users threatened individually by US law enforcement until the service died.

There’s no one to threaten. You may be able to find one or two people running the fullnode but it’d be immensely difficult to find everyone running a fullnode around the world and threaten them.

ENS has only 6 root key holders which not that many from a security perspective. Handshake has no root key holders — it’s secured by every fullnode supporting the blockchain. That’s what makes bitcoin so difficult to shut down.