Because of, you know, the threat that she poses to national security:
TSA officials got more than a peek at Rihanna as she went through airport security yesterday. The singer, appearing in good spirits, was subjected to a full body scan while traveling from LAX to New York, dressed in a gray tank top and beige trousers, with her hair pinned up in a blue bow. RiRi will be honored tonight at the 5th Annual DKMS Gala for her dedicated work in the fight against leukemia.
As usual, our safety is their priority.