I used my TWIC card for id at the airport last week, and the guy didn’t even blink at it.
On the note of crew’s not being able to get off, I’m currently on a tanker in Germany, and the crew was just in New Jersey (Danish officers, Filipino crew), and they were not allowed off of the ship. They’ve told me that they could have gotten off with an escort at a rate of $150 an hour, minimum 6 hours (I don’t know if that’s true or not). Yet the ship was in Maine before going to Jersey and they were allowed off there. I’m told it was the terminal that wouldn’t let them off.