Wait, this is the FBI. You mean they can't just knock on the door of the NSA, say "hey, use your XKEYSCORE to trace this creep", then parallel-construct an evidence chain with fictional provenance so they can nail him in court so hard all his lawyers can do is recommend taking a plea bargain?

What are we paying those guys for, anyway? What are secret police even for, if not prosecuting people you can't legally gather evidence against?