errorism is the biggest concern for Jacksonville's FBI office and there are still people of concern on the First Coast, according to a lead FBI official.
"It's the things you didn't even know to look for that will kill you in this business," said Special Agent in Charge James Casey.
Ten years after 9/11, the FBI is still focused on the River City.
Several of the 9/11 hijackers spent time in the area months before the attacks. Hijackers stayed at the Ramada Inn on University Boulevard, visited Wacko's strip club on Emerson and Craig airfield off Atlantic Boulevard.
Casey keeps the 9/11 Commission Report an arm's reach away. "I keep that book on my desk and have since it was published in 2003. It's heavily thumbed through and heavily highlighted."
The battle against terror is now a different kind of war, said Casey.
It started to change several years ago.
"Across the Middle East, when the military, intelligence agencies...roll up bad guys, inevitably they have Blackberries, smartphones, iPhones, iPads. All of that has data and all that data comes back to addresses and phone numbers and emails ... across the country including in Jacksonville," said Casey.
The FBI is sifting through more information than it ever has, said Casey. Its new facility in Jacksonville allows the agency to work more closely with local law enforcement in sharing information.
Members of the Jacksonville Sheriff's Office, Florida Department of Law Enforcement and the Navy are now all housed in the FBI building and are set up in crime-fighting task forces.
The biggest group is the Joint Terrorism Task Force, or JTTF, which meets every Tuesday inside the FBI complex to discuss new leads and people to check out.
"There are always people that pop up on our radar. Some of them go away, some of them don't go away, " said Casey.
When asked if Al-Qaeda cells are in Jacksonville, Casey replied, "Don't know or wouldn't say if I did."
Casey said part of the battle on terror was won May 1. "Was I glad he wasn't a part of the picture anymore," he said of Osama bin Laden's death.
But bin Laden's death brought new problems. "There's a new leader...he has - according to everything we've seen - maybe a different model," Casey said. "Maybe not so much an emphasis on the spectacular attack that bin Laden was always looking to do."
That complicates the FBI's job because it's harder to unravel a less complex plot that doesn't involve many people, said Casey.
"They can be done at home by a couple of people. Their chance of success goes up when they are willing to take less, and it looks to us right now (that) they are willing to take a lot less," said Casey.
He said the job can be frustrating, and agents have to learn to take it one day at time.
"I think in terms of what's out there that we don't know. Who's out there that recently came here? Who can we talk to that can tell us who is being self radicalized?" said Casey.
Those questions sometimes cause him to lose sleep.
The man in charge of the Jacksonville FBI office said every night he thinks of one thing before going to bed.
"Did we miss something (that) was there - a piece of intelligence that should have been looked at and wasn't."