Does this mean, for every person traveling, the feds can identify your social network activity and detect thought-crime? I'm interested in how they already knew which accounts belonged to who -- and how they automatically detected them as 'threats'.
Carnivore, now DSC1000, scrapes the web and inspects packets for keywords and flags potential threats. I'm pretty sure "destroy" and "America" would raise a flag in it's system.
Furthermore, finding out who accounts on twitter belong to is often fairly trivial since a good deal of people use their actual names and if not that use pseudonyms that are easily linked.
if you say "destroy america" in your tweet, it's probably going to get flagged. Odds are good the guy has his real name on his profile somewhere or a way of finding it. I know I do.