There was no centralized security detail and most airports simply hired private local security firms to do the job.
A lot of things changed after 9/11 but that was among the biggest. The TSA was born just a few months after the attack, and it has been growing and adapting ever since.
"We have to try and always stay one step ahead of what they might be plotting and planning, but we are an agile agency. Certainly much more agile than we were in the past," said Gerardo Spero, Federal Security Director for the TSA in Philadelphia.
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Spero gave Action News a behind-the-scenes look at the layers and layers of security in place at Philadelphia International Airport. In fact, those passenger screenings begin long before you reach the airport.
"It starts with basically passenger vetting when you make your reservation. It gets sent through a system and then the results come back on whether you fall into a high-risk, regular, or low-risk category," he said.
Then, of course, you have the screenings that take place before you board. Liquids, gels and aerosols have been banned on flights for years.
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Still, those are among the myriad items that are confiscated every day. Spero admits he has a hard time understanding how so many people using Philadelphia International Airport still don't know what you cannot bring onto a plane.
That includes undisclosed firearms.
"This year I believe we are up to seven or eight firearms, which if you adjust for volume is about a 30% increase over what we've seen in previous years," he said.
Brian Carolina, a supervising transportation security officer, says there is another concern besides weeding out potential terrorists. Namely, irate passengers.
"A few of the supervisors and officers have been assaulted by passengers at other airports. You have to keep that in mind. Every time they call for a supervisor it can be a myriad of things that can be going on," he said.
By the way, attacking a TSA officer is a federal offense.
Today, the TSA runs on a multi-billion dollar budget while employing more than 60,000 security personnel.
"We are all working really hard to make sure you're safe, and it's good to see that aviation is picking back up again and we will be here. We've been here all through COVID, and we will be here no matter what happens," said Spero.
The TSA is also charged with protecting our railways, mass transit, ports, pipelines and, of course, screening passengers and baggage at more than 450 U.S. airports.