>> there was a lone wolf radical on facebook, he wasn't alone for long. soon he said he was receiving up to 30 messages a day from radical groups and a barrage of violent images to fuel his supposed fury. these lone wolves have a pack of wolves out there whom they don't know and who are sort of dotting the landscape in europe, many people in africa, maybe many people in the caucus region who can unite online and become friends. >> reporter: regardless smrve, n washington want to see closer monitoring of all of them, phone calls, computer chats and the visits to 5,000 or more terrorist web sites believed to exist. especially when they download material as tamerlan tsarnaev is suspected of doing. that has spurred privacy advocates to push back saying they're already plenty of laws to handle that murky world. >> if you really can't track down every, you know,