The US are so offended that an email encryption exists that they cannot break, that they put pressure on it's owner to shut it down. How dare he provide a service that the NSA cannot hack! The nerve of that guy. It is obvious that only terrorists would use such a service because regular Americans (or any other nationality for that matter) apparently have no problem with the government tracking there email traffic because it makes the world safer.
What a load of bullshit.
If we could prove that a terrorist ever used the US postal service, would they shut that down? Would they label it a tool of traitors and spies?
Specifically, if a company has any ties to the US then they can request access to emails under the Foreign Intelligence Surveillance Act.

"I am unaware of any situation in which a service provider chose to shut down rather than comply with a court order they felt violated the constitution," said Kurt Opsahl, a lawyer with the Electronic Frontier Foundation.