Yeah, I'd think NSA has sophisticated technology to crack down, for example Ross Ulbricht (SilkRoute guy) is in jail, and so were some of the traders on it. Can you elaborate on SEC making an empty threat? Have they done it in the past? This seems like a very formal document. Is it safe to work with a ICO team while residing in US?
There is nothing stopping you or anybody living in the US to do any type of business or partner with other people, you can join an ico team and might not be fully participate in their financial process (SEC threat), your share shall be sent to you through other payment method.
Empty threat because they shall not implement such law because most of the US parliament members are involve in cryptocurrency business then ask me who will pass the law ?