...and hopefully severe searching and checking to make sure no muppet brings in a USB stick or worse.
Once worked for a big Swedish multinational who also built ship borne missile systems. They gave us laptops with tracking and encrypted hard drives that were set to wipe clean on 3 wrong passwords. Policy was no USB sticks. Everyone used them including the manager who was espousing the no USB policy. Strangely, laptops regularly went missing too. Once when burning the midnight oil at 2 a.m. and all alone on one of the rarefied levels of a 42 story "smart" building, I heard someone trying to bash down the door, fortunately I was on the phone to a co-worker and kept the line open. The perpetrator got through the street level door (RFID card), manned security in the foyer, lift operation (same RFID card but has to be programmed for that floor) but didn't succeed getting through the last line of defense which was just a swipe card controlled door, so he/she tried to force it but didn't succeed. Had to be an inside job.