It was rare for the federal security director at Chicago O’Hare to sit down with her floor-level Transportation Security Administration officers—it usually presaged a termination—and so I was nervous as I settled in across the desk from her. She was a woman in her forties with sharp blue eyes that seemed to size you up for placement in a spreadsheet. She held up a copy of the newspaper, open to the letters page. My contribution, under the headline “To Stop a Terrorist: No Lack of Ideas,” was circled in blue pen.