Just in case you're operating on the premise that you have rights... The DoJ's basically saying they can collect personal data on foreigners, and that if you talk to foreigners, you're making that information "public," even if it was an encrypted email. EFF: "...in the cases the government cites in the passage above, United States v. White and Hoffa v. United States, the Supreme Court found there is no Fourth Amendment violation if you have a private conversation with someone who happens to be a government informant and repeats what you said to the government or even surreptitiously records it. In those instances, individuals’ “misplaced confidence” that people they are communicating with won’t divulge their secrets is not enough to create a Fourth Amendment interest."
I'd be more worried about another application. If a website has administrators, moderators, founders - anyone who could view information on a web server, like forum PMs or emails - you have no privacy if they are not all in that magic protective ring of US citizenship. Effectively, it's not only impossible to expect privacy, but also impossible to expect the gov't not to use whatever they find in court against you unless you find some goofy companies pledging (truthfully!) that all their employees are US citizens.
EFF statement:
https://www.eff.org//deeplinks/2014/05/government-explains-away-fourth-amendment-protection-digital-communications
