How much would it actually cost to store all the emails that American citizens send and receive? I find it difficult to visualise a system of checks and balances approving the massive budget required to house all that data. And the technical challenge of sifting through those emails would be seriously hard. I understand that this might not be just about national security, but it could also be a power game on the part of the FBI. One has to consider how much [national security | power] this really affords [US citizens | the FBI] when measured against the gargantuan expenditure required to actually pull it off. This makes me totally skeptical. Additionally, by saying 'basically the e-mails of virtually everybody in the country' Binney demonstrates his lack of conviction and uncertainty of his own claims.
So, if his words aren't the giveaway, then two minutes of critical thinking will make the interview seem alarmist and inaccurate.