The Director of the FBI expressed concern recently that technological advances might render practically meaningful the First Amendment's right to free assembly and the Fourth Amendment's right to freedom from unreasonable search. Instead, it might be necessary to get a court order to snoop on U.S. citizens. Poor G-man.
Incidentally, nothing in the tech interferes with government collection of metadata, only with the encrypted message contents. Mapping networks of connected individuals is apparently still fair game for government agencies interested in snooping warrentlessly into the relationships of those presumed innocent.
UPDATE: The Director of the Federal Bureau of Investigation is asking Congress to create federal law that would interfere with genuine privacy of the sort already required by federal law in areas like credit card transactions and health care privacy. Apparently those technologies are too dangerous for Americans, after all.