Update from ATL (coming in from South America, 5 hours delayed, so arriving at 10 pm): "the single agent at TSA security in the international terminal saw the line of 1000 people and just closed the checkpoint. Which meant all 1000 people had to queue up outside in 19 degree temps to wait for shuttle buses to transport us to the domestic terminal. And those buses—repurposed from shuttling people to the parking lots—only carried a dozen or so people at a time."