content: This is why metadata is enough, especially when "network investigative techniques" or "computer network exploitation" or hacking, is normal. If you can watch who is talking to who, you know better who to hack, this is why the Snowden/Poitras/Greenwald doc also recommended Tor, which helps obfuscate that. Even then, its still a lot of breadcrumbs lying around. Edit: Its still greenwald@gmail.com talking to snowden@gmail.com