(CBS News) WASHINGTON - Security for President Barack Obama's second inauguration will, of course, be extremely tight. Uniformed police will be everywhere in Washington.
During President Obama's first inauguration, there was a threat taken so seriously that counter-terrorism agents seemed to be everywhere in the crowd of two million. In East Africa, people were taken into custody and given lie detector tests by the FBI. In the end, the tip turned out to be wrong, but it gave a young administration, on its very first day, a picture of what can go on behind the scenes of a major event.
For this inauguration, some of the security is meant to be obvious. The Coast Guard will shut down the Potomac River.
But some of the security is meant to be nearly invisible. At Union Station, two men who could have been waiting for a train were actually DHS Behavioral Detection Officers who blend into the crowd. Trained to look for suspicious behavior among passengers, they were in communication with teams of armed TSA officers.
At the FBI's Washington Field Office, a command center is gearing up to coordinate the response to any threat that may emerge. Kimberly Howell is in charge of a team of intelligence analysts that looks at each one.
"There are always threats coming in, the inauguration is no different," Howell said. "It's our job to assess those threats and to evaluate them."
At FBI Headquarters as they followed unfolding events in Algeria at the Strategic Information and Operations Center, Deputy Assistant Director Jenny Ley talked about the daunting challenge they face before an event like the inauguration.
"You can't just cancel it, you can't call it off, you have to be working behind the scenes diligently and aggressively to make sure that that threat does not occur," Ley said.
"At this time, we actually have no credible threats to this inauguration, but that does not mean behind the scenes we are not still constantly evaluating, constantly looking at everything that's coming in," she added.
The serious threat that occurred during the president's last inauguration was related to al-Qaeda. It was information from a source who said there was a plot to attack the inauguration by an al-Qaeda affiliate in Somalia. It meant running leads down in Kenya, Uganda and Somalia and at the same time looking for suspects in the United States. It meant working twenty-four-seven for about three days and the threat was resolved right around the time the president help up his right hand. It came right down to the wire.