Dumb At The Checkpoint

During this trip, I saw a lady trying to get though security. I think she understood in a single-celled sort of way what a metal detector was, but I'm also sure she had no idea why it was there. She had on this huge metal belt buckle, and kept setting the detector off. And each time the TSA officer would stop her, she would insist that it was OK, it was just her belt buckle, and try to head through anyway. Meanwhile, the twenty people behind her, late for their flights, could only watch and bang their heads on the table. And I wish I could say this was atypical.
If I was TSA, I think I'd shoot myself, and then someone else.