When he heard about the bombings in Boston. David Gomez, a former Senior Assistant Special Agent-in-Charge for Counter-terrorism and Intelligence at the FBI's Seattle Field Office, began to tweet. (He's @allthingshls). For years, he was one of the bureau's top CT agents and criminal profilers, and so he knows his brief. I asked Gomez to answer a few questions about how the FBI will move forward with what surely will prove to be a complex investigation. 

Q: What's the FBI's role now, and why was it so quick to take control of the investigation?

A: "The FBI investigates bombings. And a bombing is automatically assumed to be a terrorism event. This was true prior to 9/11, but after, it became clear in the law, and by presidential directive that we were the lead agency in a terrorism event. A lot of what's going on right now is, basically, working with the city and knowing that since we're going to be late to the scene — the police have first response and emergency response — to figure out who is going to take custody of the evidence and what labs are going to process it."

Q: The Special Agent in Charge of the FBI Field Office in Boston, Rick DesLauriers, referred to this as a "potential terrorism" event. Why use the word potential?

A: "I wonder if that was directed from our headquarters, or maybe from the White House, because I noticed that the president didn't use the term. Look, to the people on the ground, our guys, it's a criminal investigation. They're not collecting evidence to make a terrorism case. They're collecting evidence to prove a bombing. Absent a motive or claim of responsibility, it's just a bombing. But after 9/11, there's a presumption in law that a bombing is a terrorist attack."

Q: How is a case like this going to be organized internally?

A: "You're going to be getting so many tips coming in, that you have to essentially bifurcate it. Some of our people will go through all the forensics evidence. Others will look at the local intelligence picture, to figure out which groups there are and what we know about them. Then you have a team working all the data dumps we're going to be getting. And then you've got to find a team to work through all of the tips, most of which are going to be crap, but you can't ignore them because you might find a nugget. Every FBI field office in the country is going to have people working on this."

Q: I was reading on Twitter that it would be easy for the FBI to figure out who made a call to remotely detonate a bomb if it were triggered by radio frequencies. Is that true?

A: "Would it be easy to get the data? Yes. You'd get call records from towers around the area for an hour or two before the attacks, or whatever period of time. But analyzing it is really difficult; you might get 12,000 different numbers."

Q: So it's not as easy as it looks on TV?

A: "These things take a lot of time."

Q: Why is there so much debate about the word "terrorism?"  And I was wondering: If a guy goes into a school and murders 20 children to make a point, why is that any different than what happened today?

A: "There is a difference between public perception and what the professionals think. To me, terrorism has always been about the messaging, and not about the event. A guy blows up his neighbor's house; it's a bombing but it's not terrorism. The Weathermen blew up a bathroom in the Capitol to send a message that no place was safe and we're gonna take over the world. That's terrorism.  Tragedy is different than terrorism. A terrifying traffic event is not the same thing as terrorism."

Q: But the U.S. Attorney will make the decision about what to call it?

A: "Yes. And you can bet they're sitting in there, side by side, with the team."

Q: Is there any difference between a domestic terrorism investigation and one that involves foreign groups?

A: "After 9/11, for domestic terrorism investigations, the FBI adopted a lot of rules that you have to follow. If the crime is though to have been domestic as opposed to a transnational group, constitutional issues come into play. But really, the issue of 'terrorism' only comes out in the charging. Right now, the focus is on proving the bombing, figuring out who was involved, looking at the story the forensic evidence tells us."