Sure jimmie.

TSA and other airport security measures have always focused on the "things" that cause security concerns. Guns, bombs, flammables, etc. Finding them and preventing them from getting on an aircraft. But that has been shown to not work so well. The hijackers of 9/11 used that against us and thereby created the situation we have now. They brought non-prohibited items on board and used them to kill 3000+ people.

TSA cannot prevent every possible weapon or item that can be used as a weapon from being brought on board an aircraft, no matter how hard we try or the policies they put in place. Just not possible. But what can be done is prevent those folks that want to do harm to that aircraft and those passengers from ever getting on board. That’s what the BDO’s and some other programs are designed to do. BDO’s can’t tell if a person is a terrorist, but they can tell if a person is exhibiting the signs of someone hiding something significant, and they can use that information to find out if what they are hiding is the intent to harm an aircraft or the passengers.

Its not 100% perfect. People hide all kind of things for all kinds of reasons. Other issues can get in the way of Behavior Detection working properly as well. Medical, emotional, chemical. But it does provide us with another layer of prevention / security prior to someone boarding an aircraft.

Some of the folks out there have complained about the cost of the program. Perspective. How much did the hijackers of 9/11 cost the USA with their act of terrorism? Not just the cost of the buildings and the people, but the cost to the airline industry, the cost of sending the military into Afghanistan (I’m not going to discuss Iraq)? The total cost to us for the actions of those 19 terrorists is in the high trillions, and continues to mount to this day. A few billion for the TSA and its programs/equipment is pocket change in comparison. Perspective.