Sorry for the ambiguity about the location. It was at T4 at JFK. Unless I missed it, it doesn't seem that anyone has answered the question as to whether it is possible that a passport is actually required to pass into a concourse that only has international flights.

The reason that I prefer to show my DL, instead of passport, is because before an international flight, I would rather lose my DL than my passport. I don't worry about their seeing the address on it, because I don't live at that address, so it would be a bad choice of a place to rob. Also, I until recently, I didn't even use my DL to pass thorugh security, because I used by SIDA ID, which usually works much better, because then ID checks usually don't ask questions.